[PATCH v3 11/59] dmaengine: Move slave caps to dma_device

Laurent Pinchart laurent.pinchart at ideasonboard.com
Wed Oct 22 14:06:47 PDT 2014


Hi Maxime,

Thank you for the patch.

On Wednesday 22 October 2014 17:43:25 Maxime Ripard wrote:
> The previous code was relying on the fact that the slave_caps were to be
> defined on a per channel basis.
> 
> However, this proved to be a bit overkill, since every driver filling these
> so far were hardcoding it, disregarding which channel was actually given.
> 
> Add these capabilities to the dma_device structure, so that drivers can just
> provide them at probe time, and be done with it.
> 
> Signed-off-by: Maxime Ripard <maxime.ripard at free-electrons.com>

Acked-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

> ---
>  include/linux/dmaengine.h | 17 +++++++++++++++++
>  1 file changed, 17 insertions(+)
> 
> diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
> index 6b74d9d8977e..98f8163dfbac 100644
> --- a/include/linux/dmaengine.h
> +++ b/include/linux/dmaengine.h
> @@ -593,6 +593,14 @@ struct dma_tx_state {
>   * @fill_align: alignment shift for memset operations
>   * @dev_id: unique device ID
>   * @dev: struct device reference for dma mapping api
> + * @src_addr_widths: bit mask of src addr widths the device supports
> + * @dst_addr_widths: bit mask of dst addr widths the device supports
> + * @directions: bit mask of slave direction the device supports since
> + * 	the enum dma_transfer_direction is not defined as bits for
> + * 	each type of direction, the dma controller should fill (1 <<
> + * 	<TYPE>) and same should be checked by controller as well
> + * @residue_granularity: granularity of the transfer residue reported
> + *	by tx_status
>   * @device_alloc_chan_resources: allocate resources and return the
>   *	number of allocated descriptors
>   * @device_free_chan_resources: release DMA channel's resources
> @@ -643,6 +651,10 @@ struct dma_device {
>  	struct device *dev;
> 
>  	bool generic_slave_caps;
> +	u32 src_addr_widths;
> +	u32 dst_addr_widths;
> +	u32 directions;
> +	enum dma_residue_granularity residue_granularity;
> 
>  	int (*device_alloc_chan_resources)(struct dma_chan *chan);
>  	void (*device_free_chan_resources)(struct dma_chan *chan);
> @@ -807,6 +819,11 @@ static inline int dma_get_slave_caps(struct dma_chan
> *chan, struct dma_slave_cap if (device->generic_slave_caps)
>  		return -ENXIO;
> 
> +	caps->src_addr_widths = device->src_addr_widths;
> +	caps->dst_addr_widths = device->dst_addr_widths;
> +	caps->directions = device->directions;
> +	caps->residue_granularity = device->residue_granularity;
> +
>  	caps->cmd_pause = !!device->device_pause;
>  	caps->cmd_terminate = !!device->device_terminate_all;

-- 
Regards,

Laurent Pinchart




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