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

From: Peter Ujfalusi
Date: Tue Mar 15 2016 - 04:56:04 EST


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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