Re: [PATCH 1/2] dmaengine: Move icg helpers to global header

[Ludovic Desroches <ludovic.desroches@atmel.com>]

On Wed, May 27, 2015 at 04:01:52PM +0200, Maxime Ripard wrote:
> Now that we can have ICGs set for both the source and destination (using
> the icg field of struct data_chunk) or for only the source or the
> destination (using the dst_icg or src_icg respectively), and that these
> fields can be ignored depending on other parameters (src_inc, src_sgl,
> etc.), the logic to get the actual ICG value can be quite tricky.
> 
> The XDMAC driver was already implementing it, but since we will need it in
> other drivers, we can move it to the main header file.
> 
> Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>

> ---
>  drivers/dma/at_xdmac.c    | 46 ++++------------------------------------------
>  include/linux/dmaengine.h | 27 +++++++++++++++++++++++++++
>  2 files changed, 31 insertions(+), 42 deletions(-)
> 
> diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c
> index 9b602a67d40d..80e46e571bdd 100644
> --- a/drivers/dma/at_xdmac.c
> +++ b/drivers/dma/at_xdmac.c
> @@ -862,20 +862,8 @@ at_xdmac_interleaved_queue_desc(struct dma_chan *chan,
>  
>  	desc->lld.mbr_sa = src;
>  	desc->lld.mbr_da = dst;
> -
> -	if (xt->src_inc && xt->src_sgl) {
> -		if (chunk->src_icg)
> -			desc->lld.mbr_sus = chunk->src_icg;
> -		else
> -			desc->lld.mbr_sus = chunk->icg;
> -	}
> -
> -	if (xt->dst_inc && xt->dst_sgl) {
> -		if (chunk->dst_icg)
> -			desc->lld.mbr_dus = chunk->dst_icg;
> -		else
> -			desc->lld.mbr_dus = chunk->icg;
> -	}
> +	desc->lld.mbr_sus = dmaengine_get_src_icg(xt, chunk);
> +	desc->lld.mbr_dus = dmaengine_get_dst_icg(xt, chunk);
>  
>  	desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV3
>  		| AT_XDMAC_MBR_UBC_NDEN
> @@ -895,32 +883,6 @@ at_xdmac_interleaved_queue_desc(struct dma_chan *chan,
>  	return desc;
>  }
>  
> -static size_t at_xdmac_get_icg(bool inc, bool sgl, size_t icg, size_t dir_icg)
> -{
> -	if (inc) {
> -		if (dir_icg)
> -			return dir_icg;
> -		else if (sgl)
> -			return icg;
> -	}
> -
> -	return 0;
> -}
> -
> -static size_t at_xdmac_get_dst_icg(struct dma_interleaved_template *xt,
> -				   struct data_chunk *chunk)
> -{
> -	return at_xdmac_get_icg(xt->dst_inc, xt->dst_sgl,
> -				chunk->icg, chunk->dst_icg);
> -}
> -
> -static size_t at_xdmac_get_src_icg(struct dma_interleaved_template *xt,
> -				   struct data_chunk *chunk)
> -{
> -	return at_xdmac_get_icg(xt->src_inc, xt->src_sgl,
> -				chunk->icg, chunk->src_icg);
> -}
> -
>  static struct dma_async_tx_descriptor *
>  at_xdmac_prep_interleaved(struct dma_chan *chan,
>  			  struct dma_interleaved_template *xt,
> @@ -950,8 +912,8 @@ at_xdmac_prep_interleaved(struct dma_chan *chan,
>  
>  		chunk = xt->sgl + i;
>  
> -		dst_icg = at_xdmac_get_dst_icg(xt, chunk);
> -		src_icg = at_xdmac_get_src_icg(xt, chunk);
> +		dst_icg = dmaengine_get_dst_icg(xt, chunk);
> +		src_icg = dmaengine_get_src_icg(xt, chunk);
>  
>  		src_skip = chunk->size + src_icg;
>  		dst_skip = chunk->size + dst_icg;
> diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
> index 8faf6a2dd9d8..43a9a397b2d7 100644
> --- a/include/linux/dmaengine.h
> +++ b/include/linux/dmaengine.h
> @@ -899,6 +899,33 @@ static inline int dma_maxpq(struct dma_device *dma, enum dma_ctrl_flags flags)
>  	BUG();
>  }
>  
> +static inline size_t dmaengine_get_icg(bool inc, bool sgl, size_t icg,
> +				      size_t dir_icg)
> +{
> +	if (inc) {
> +		if (dir_icg)
> +			return dir_icg;
> +		else if (sgl)
> +			return icg;
> +	}
> +
> +	return 0;
> +}
> +
> +static inline size_t dmaengine_get_dst_icg(struct dma_interleaved_template *xt,
> +					   struct data_chunk *chunk)
> +{
> +	return dmaengine_get_icg(xt->dst_inc, xt->dst_sgl,
> +				 chunk->icg, chunk->dst_icg);
> +}
> +
> +static inline size_t dmaengine_get_src_icg(struct dma_interleaved_template *xt,
> +					   struct data_chunk *chunk)
> +{
> +	return dmaengine_get_icg(xt->src_inc, xt->src_sgl,
> +				 chunk->icg, chunk->src_icg);
> +}
> +
>  /* --- public DMA engine API --- */
>  
>  #ifdef CONFIG_DMA_ENGINE
> -- 
> 2.4.1
>