Re: [PATCH v1 2/2] dmaengine: fsl-edma: add edma src ID check at request channel

[Vinod Koul <vkoul@kernel.org>]

On 21-06-24, 18:49, Joy Zou wrote:
> Check src ID to detect misuse of same src ID for multiple DMA channels.
> 
> Signed-off-by: Joy Zou <joy.zou@nxp.com>
> ---
>  drivers/dma/fsl-edma-main.c | 22 ++++++++++++++++++++++
>  1 file changed, 22 insertions(+)
> 
> diff --git a/drivers/dma/fsl-edma-main.c b/drivers/dma/fsl-edma-main.c
> index d4f29ece69f5..47939d010e59 100644
> --- a/drivers/dma/fsl-edma-main.c
> +++ b/drivers/dma/fsl-edma-main.c
> @@ -100,6 +100,22 @@ static irqreturn_t fsl_edma_irq_handler(int irq, void *dev_id)
>  	return fsl_edma_err_handler(irq, dev_id);
>  }
>  
> +static bool fsl_edma_srcid_in_use(struct fsl_edma_engine *fsl_edma, u32 srcid)
> +{
> +	struct fsl_edma_chan *fsl_chan;
> +	int i;
> +
> +	for (i = 0; i < fsl_edma->n_chans; i++) {
> +		fsl_chan = &fsl_edma->chans[i];
> +
> +		if (fsl_chan->srcid && srcid == fsl_chan->srcid) {
> +			dev_err(&fsl_chan->pdev->dev, "The srcid is using! Can't use repeatly.");

Better message would be: "The srcid is in use, cant use!"

wdyt?

> +			return true;
> +		}
> +	}
> +	return false;
> +}
> +
>  static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
>  		struct of_dma *ofdma)
>  {
> @@ -117,6 +133,10 @@ static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
>  	list_for_each_entry_safe(chan, _chan, &fsl_edma->dma_dev.channels, device_node) {
>  		if (chan->client_count)
>  			continue;
> +
> +		if (fsl_edma_srcid_in_use(fsl_edma, dma_spec->args[1]))
> +			return NULL;
> +
>  		if ((chan->chan_id / chans_per_mux) == dma_spec->args[0]) {
>  			chan = dma_get_slave_channel(chan);
>  			if (chan) {
> @@ -161,6 +181,8 @@ static struct dma_chan *fsl_edma3_xlate(struct of_phandle_args *dma_spec,
>  			continue;
>  
>  		fsl_chan = to_fsl_edma_chan(chan);
> +		if (fsl_edma_srcid_in_use(fsl_edma, dma_spec->args[0]))
> +			return NULL;
>  		i = fsl_chan - fsl_edma->chans;
>  
>  		fsl_chan->priority = dma_spec->args[1];
> -- 
> 2.37.1

-- 
~Vinod