Re: [PATCH v3 04/13] media: ti: j721e-csi2rx: allocate DMA channel based on context index

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Rishikesh,

Thank you for the patch.

On Thu, Apr 17, 2025 at 12:25:45PM +0530, Rishikesh Donadkar wrote:
> From: Pratyush Yadav <p.yadav@ti.com>
> 
> With multiple contexts, there needs to be a different DMA channel for
> each context. Earlier, the DMA channel name was hard coded to "rx0" for
> the sake of simplicity. Generate the DMA channel name based on its index
> and get the channel corresponding to the context.
> 
> Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
> Signed-off-by: Jai Luthra <j-luthra@ti.com>
> Reviewed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
> Signed-off-by: Rishikesh Donadkar <r-donadkar@ti.com>
> ---
>  drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c b/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
> index d03dc4e56d306..523c890139098 100644
> --- a/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
> +++ b/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
> @@ -1015,6 +1015,7 @@ static int ti_csi2rx_init_dma(struct ti_csi2rx_ctx *ctx)
>  	struct dma_slave_config cfg = {
>  		.src_addr_width = DMA_SLAVE_BUSWIDTH_16_BYTES,
>  	};
> +	char name[32];

That seems a bit long. 5 characters should be enough.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

>  	int ret;
>  
>  	INIT_LIST_HEAD(&ctx->dma.queue);
> @@ -1023,7 +1024,8 @@ static int ti_csi2rx_init_dma(struct ti_csi2rx_ctx *ctx)
>  
>  	ctx->dma.state = TI_CSI2RX_DMA_STOPPED;
>  
> -	ctx->dma.chan = dma_request_chan(ctx->csi->dev, "rx0");
> +	snprintf(name, sizeof(name), "rx%u", ctx->idx);
> +	ctx->dma.chan = dma_request_chan(ctx->csi->dev, name);
>  	if (IS_ERR(ctx->dma.chan))
>  		return PTR_ERR(ctx->dma.chan);
>  

-- 
Regards,

Laurent Pinchart