Re: [PATCH v2 4/5] mmc: davinci: don't use dma platform resources

[Peter Ujfalusi]

 On 03/15/16 00:54, David Lechner wrote:
> The davinci arch now has dma_slave_map tables for dma resources, so it is
> no longer necessary to pass dma resources through the platform device.
> 
> Signed-off-by: David Lechner <david@xxxxxxxxxxxxxx>
> ---
> 
> v2 changes: Remove platform_get_resource completly instead of just ignoring it.
> 
> 
>  drivers/mmc/host/davinci_mmc.c | 19 ++-----------------
>  1 file changed, 2 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/mmc/host/davinci_mmc.c b/drivers/mmc/host/davinci_mmc.c
> index 8d10a92..dc96401 100644
> --- a/drivers/mmc/host/davinci_mmc.c
> +++ b/drivers/mmc/host/davinci_mmc.c
> @@ -202,7 +202,6 @@ struct mmc_davinci_host {
>  	u32 buffer_bytes_left;
>  	u32 bytes_left;
>  
> -	u32 rxdma, txdma;
>  	struct dma_chan *dma_tx;
>  	struct dma_chan *dma_rx;
>  	bool use_dma;
> @@ -520,16 +519,14 @@ static int __init davinci_acquire_dma_channels(struct mmc_davinci_host *host)
>  	dma_cap_set(DMA_SLAVE, mask);
>  
>  	host->dma_tx =
> -		dma_request_slave_channel_compat(mask, edma_filter_fn,
> -				&host->txdma, mmc_dev(host->mmc), "tx");
> +		dma_request_slave_channel(mmc_dev(host->mmc), "tx");

you would need to use dma_request_chan() to be able to rely on the legacy
channel mapping.
I have staged commits for converting all daVinci and OMAP drivers, I'll attach
the patch I have for davinci-mmc for reference.
When we convert to use the dma_request_chan() we can handle deferred probing
also...



>  	if (!host->dma_tx) {
>  		dev_err(mmc_dev(host->mmc), "Can't get dma_tx channel\n");
>  		return -ENODEV;
>  	}
>  
>  	host->dma_rx =
> -		dma_request_slave_channel_compat(mask, edma_filter_fn,
> -				&host->rxdma, mmc_dev(host->mmc), "rx");
> +		dma_request_slave_channel(mmc_dev(host->mmc), "rx");
>  	if (!host->dma_rx) {
>  		dev_err(mmc_dev(host->mmc), "Can't get dma_rx channel\n");
>  		r = -ENODEV;
> @@ -1251,18 +1248,6 @@ static int __init davinci_mmcsd_probe(struct platform_device *pdev)
>  	host = mmc_priv(mmc);
>  	host->mmc = mmc;	/* Important */
>  
> -	r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
> -	if (!r)
> -		dev_warn(&pdev->dev, "RX DMA resource not specified\n");
> -	else
> -		host->rxdma = r->start;
> -
> -	r = platform_get_resource(pdev, IORESOURCE_DMA, 1);
> -	if (!r)
> -		dev_warn(&pdev->dev, "TX DMA resource not specified\n");
> -	else
> -		host->txdma = r->start;
> -
>  	host->mem_res = mem;
>  	host->base = devm_ioremap(&pdev->dev, mem->start, mem_size);
>  	if (!host->base)
> 


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