Re: [PATCH] mmc: omap_hsmmc: Use dma_request_chan() for requesting DMA channel

[Ulf Hansson]

On 29 April 2016 at 15:06, Peter Ujfalusi <peter.ujfalusi@xxxxxx> wrote:
> With the new dma_request_chan() the client driver does not need to look for
> the DMA resource and it does not need to pass filter_fn anymore.
> By switching to the new API the driver can now support deferred probing
> against DMA.
>
> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx>

Thanks, applied for next!

Kind regards
Uffe

> ---
>  drivers/mmc/host/omap_hsmmc.c | 50 +++++++++----------------------------------
>  1 file changed, 10 insertions(+), 40 deletions(-)
>
> diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
> index e9d75c6dd516..06a167292820 100644
> --- a/drivers/mmc/host/omap_hsmmc.c
> +++ b/drivers/mmc/host/omap_hsmmc.c
> @@ -32,7 +32,6 @@
>  #include <linux/of_irq.h>
>  #include <linux/of_gpio.h>
>  #include <linux/of_device.h>
> -#include <linux/omap-dmaengine.h>
>  #include <linux/mmc/host.h>
>  #include <linux/mmc/core.h>
>  #include <linux/mmc/mmc.h>
> @@ -1989,8 +1988,6 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
>         struct resource *res;
>         int ret, irq;
>         const struct of_device_id *match;
> -       dma_cap_mask_t mask;
> -       unsigned tx_req, rx_req;
>         const struct omap_mmc_of_data *data;
>         void __iomem *base;
>
> @@ -2120,44 +2117,17 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
>
>         omap_hsmmc_conf_bus_power(host);
>
> -       if (!pdev->dev.of_node) {
> -               res = platform_get_resource_byname(pdev, IORESOURCE_DMA, "tx");
> -               if (!res) {
> -                       dev_err(mmc_dev(host->mmc), "cannot get DMA TX channel\n");
> -                       ret = -ENXIO;
> -                       goto err_irq;
> -               }
> -               tx_req = res->start;
> -
> -               res = platform_get_resource_byname(pdev, IORESOURCE_DMA, "rx");
> -               if (!res) {
> -                       dev_err(mmc_dev(host->mmc), "cannot get DMA RX channel\n");
> -                       ret = -ENXIO;
> -                       goto err_irq;
> -               }
> -               rx_req = res->start;
> -       }
> -
> -       dma_cap_zero(mask);
> -       dma_cap_set(DMA_SLAVE, mask);
> -
> -       host->rx_chan =
> -               dma_request_slave_channel_compat(mask, omap_dma_filter_fn,
> -                                                &rx_req, &pdev->dev, "rx");
> -
> -       if (!host->rx_chan) {
> -               dev_err(mmc_dev(host->mmc), "unable to obtain RX DMA engine channel\n");
> -               ret = -ENXIO;
> +       host->rx_chan = dma_request_chan(&pdev->dev, "rx");
> +       if (IS_ERR(host->rx_chan)) {
> +               dev_err(mmc_dev(host->mmc), "RX DMA channel request failed\n");
> +               ret = PTR_ERR(host->rx_chan);
>                 goto err_irq;
>         }
>
> -       host->tx_chan =
> -               dma_request_slave_channel_compat(mask, omap_dma_filter_fn,
> -                                                &tx_req, &pdev->dev, "tx");
> -
> -       if (!host->tx_chan) {
> -               dev_err(mmc_dev(host->mmc), "unable to obtain TX DMA engine channel\n");
> -               ret = -ENXIO;
> +       host->tx_chan = dma_request_chan(&pdev->dev, "tx");
> +       if (IS_ERR(host->tx_chan)) {
> +               dev_err(mmc_dev(host->mmc), "TX DMA channel request failed\n");
> +               ret = PTR_ERR(host->tx_chan);
>                 goto err_irq;
>         }
>
> @@ -2215,9 +2185,9 @@ err_slot_name:
>         mmc_remove_host(mmc);
>  err_irq:
>         device_init_wakeup(&pdev->dev, false);
> -       if (host->tx_chan)
> +       if (!IS_ERR_OR_NULL(host->tx_chan))
>                 dma_release_channel(host->tx_chan);
> -       if (host->rx_chan)
> +       if (!IS_ERR_OR_NULL(host->rx_chan))
>                 dma_release_channel(host->rx_chan);
>         pm_runtime_dont_use_autosuspend(host->dev);
>         pm_runtime_put_sync(host->dev);
> --
> 2.8.1
>