mmc: mxs-mmc: move to use generic DMA helper

With the generic DMA device tree helper supported by mxs-dma driver,
client devices only need to call dma_request_slave_channel() for
requesting a DMA channel from dmaengine.

Since mxs is a DT only platform now, along with the changes, the non-DT
case checking in probe function also gets cleaned up.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Chris Ball <cjb@laptop.org>
Cc: linux-mmc@vger.kernel.org
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

2 files changed, 13 insertions, 47 deletions

diff --git a/Documentation/devicetree/bindings/mmc/mxs-mmc.txt b/Documentation/devicetree/bindings/mmc/mxs-mmc.txt
index 54949f6faede..515addc20070 100644
--- a/Documentation/devicetree/bindings/mmc/mxs-mmc.txt
+++ b/Documentation/devicetree/bindings/mmc/mxs-mmc.txt
@@ -9,15 +9,19 @@ and the properties used by the mxsmmc driver.
 Required properties:
 - compatible: Should be "fsl,<chip>-mmc".  The supported chips include
   imx23 and imx28.
-- interrupts: Should contain ERROR and DMA interrupts
-- fsl,ssp-dma-channel: APBH DMA channel for the SSP
+- interrupts: Should contain ERROR interrupt number
+- dmas: DMA specifier, consisting of a phandle to DMA controller node
+  and SSP DMA channel ID.
+  Refer to dma.txt and fsl-mxs-dma.txt for details.
+- dma-names: Must be "rx-tx".
 
 Examples:
 
 ssp0: ssp@80010000 {
         compatible = "fsl,imx28-mmc";
         reg = <0x80010000 2000>;
-        interrupts = <96 82>;
-        fsl,ssp-dma-channel = <0>;
+        interrupts = <96>;
+        dmas = <&dma_apbh 0>;
+        dma-names = "rx-tx";
         bus-width = <8>;
 };
diff --git a/drivers/mmc/host/mxs-mmc.c b/drivers/mmc/host/mxs-mmc.c
index 4efe3021b217..4fdc71113e6d 100644
--- a/drivers/mmc/host/mxs-mmc.c
+++ b/drivers/mmc/host/mxs-mmc.c
@@ -548,22 +548,6 @@ static const struct mmc_host_ops mxs_mmc_ops = {
         .enable_sdio_irq = mxs_mmc_enable_sdio_irq,
 };
 
-static bool mxs_mmc_dma_filter(struct dma_chan *chan, void *param)
-{
-        struct mxs_mmc_host *host = param;
-        struct mxs_ssp *ssp = &host->ssp;
-
-        if (!mxs_dma_is_apbh(chan))
-                return false;
-
-        if (chan->chan_id != ssp->dma_channel)
-                return false;
-
-        chan->private = &ssp->dma_data;
-
-        return true;
-}
-
 static struct platform_device_id mxs_ssp_ids[] = {
         {
                 .name = "imx23-mmc",
@@ -591,20 +575,17 @@ static int mxs_mmc_probe(struct platform_device *pdev)
         struct device_node *np = pdev->dev.of_node;
         struct mxs_mmc_host *host;
         struct mmc_host *mmc;
-        struct resource *iores, *dmares;
+        struct resource *iores;
         struct pinctrl *pinctrl;
-        int ret = 0, irq_err, irq_dma;
-        dma_cap_mask_t mask;
+        int ret = 0, irq_err;
         struct regulator *reg_vmmc;
         enum of_gpio_flags flags;
         struct mxs_ssp *ssp;
         u32 bus_width = 0;
 
         iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-        dmares = platform_get_resource(pdev, IORESOURCE_DMA, 0);
         irq_err = platform_get_irq(pdev, 0);
-        irq_dma = platform_get_irq(pdev, 1);
-        if (!iores || irq_err < 0 || irq_dma < 0)
+        if (!iores || irq_err < 0)
                 return -EINVAL;
 
         mmc = mmc_alloc_host(sizeof(struct mxs_mmc_host), &pdev->dev);
@@ -620,23 +601,7 @@ static int mxs_mmc_probe(struct platform_device *pdev)
                 goto out_mmc_free;
         }
 
-        if (np) {
-                ssp->devid = (enum mxs_ssp_id) of_id->data;
-                /*
-                 * TODO: This is a temporary solution and should be changed
-                 * to use generic DMA binding later when the helpers get in.
-                 */
-                ret = of_property_read_u32(np, "fsl,ssp-dma-channel",
-                                           &ssp->dma_channel);
-                if (ret) {
-                        dev_err(mmc_dev(host->mmc),
-                                "failed to get dma channel\n");
-                        goto out_mmc_free;
-                }
-        } else {
-                ssp->devid = pdev->id_entry->driver_data;
-                ssp->dma_channel = dmares->start;
-        }
+        ssp->devid = (enum mxs_ssp_id) of_id->data;
 
         host->mmc = mmc;
         host->sdio_irq_en = 0;
@@ -666,10 +631,7 @@ static int mxs_mmc_probe(struct platform_device *pdev)
 
         mxs_mmc_reset(host);
 
-        dma_cap_zero(mask);
-        dma_cap_set(DMA_SLAVE, mask);
-        ssp->dma_data.chan_irq = irq_dma;
-        ssp->dmach = dma_request_channel(mask, mxs_mmc_dma_filter, host);
+        ssp->dmach = dma_request_slave_channel(&pdev->dev, "rx-tx");
         if (!ssp->dmach) {
                 dev_err(mmc_dev(host->mmc),
                         "%s: failed to request dma\n", __func__);