Re: [PATCH v2 6/9] iio: buffer-dmaengine: Use dma_slave_caps bus width accessors

On Mon, 10 Aug 2026 16:06:47 +0100
Nuno Sá <[email protected]> wrote:

> Query the minimum supported source and destination bus widths through
> the new dma_slave_caps_get_{src,dst}_width_min() helpers rather than
> decoding the raw legacy u32 width masks. This keeps the buffer working
> with DMA controllers that advertise bus widths via the new bitmap
> representation.
> 
> Reviewed-by: Frank Li <[email protected]>
> Signed-off-by: Nuno Sá <[email protected]>
I'm currently assuming this will all go through a single tree
(and not mine) As such

Acked-by: Jonathan Cameron <[email protected]>

> ---
>  drivers/iio/buffer/industrialio-buffer-dmaengine.c | 15 +++++++--------
>  1 file changed, 7 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/iio/buffer/industrialio-buffer-dmaengine.c b/drivers/iio/buffer/industrialio-buffer-dmaengine.c
> index 98acce909854..855e3662cd3d 100644
> --- a/drivers/iio/buffer/industrialio-buffer-dmaengine.c
> +++ b/drivers/iio/buffer/industrialio-buffer-dmaengine.c
> @@ -229,14 +229,13 @@ static struct iio_buffer *iio_dmaengine_buffer_alloc(struct dma_chan *chan)
>  		return ERR_PTR(-ENOMEM);
>  
>  	/* Needs to be aligned to the maximum of the minimums */
> -	if (caps.src_addr_widths)
> -		src_width = __ffs(caps.src_addr_widths);
> -	else
> -		src_width = 1;
> -	if (caps.dst_addr_widths)
> -		dest_width = __ffs(caps.dst_addr_widths);
> -	else
> -		dest_width = 1;
> +	src_width = dma_slave_caps_get_src_width_min(&caps);
> +	if (src_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
> +		src_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
> +	dest_width = dma_slave_caps_get_dst_width_min(&caps);
> +	if (dest_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
> +		dest_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
> +
>  	width = max(src_width, dest_width);
>  
>  	INIT_LIST_HEAD(&dmaengine_buffer->active);
>