[PATCH v7 05/16] media: ti: j721e-csi2rx: allocate DMA channel based on context index

Rishikesh Donadkar posted 16 patches 3 weeks ago
[PATCH v7 05/16] media: ti: j721e-csi2rx: allocate DMA channel based on context index
Posted by Rishikesh Donadkar 3 weeks ago
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>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Yemike Abhilash Chandra <y-abhilashchandra@ti.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 d4e6d6b5b2f7..99a721e46d54 100644
--- a/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
+++ b/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
@@ -1039,9 +1039,11 @@ 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[5];
 	int ret;
 
-	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);
 
-- 
2.34.1
Re: [PATCH v7 05/16] media: ti: j721e-csi2rx: allocate DMA channel based on context index
Posted by Tomi Valkeinen 1 week, 3 days ago
On 11/09/2025 13:28, 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>
> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Reviewed-by: Yemike Abhilash Chandra <y-abhilashchandra@ti.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 d4e6d6b5b2f7..99a721e46d54 100644
> --- a/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
> +++ b/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
> @@ -1039,9 +1039,11 @@ 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[5];
>  	int ret;
>  
> -	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);
>  

Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>

 Tomi