3 files changed, 125 insertions, 4 deletions

diff --git a/Documentation/devicetree/bindings/dma/fsl-imx-dma.txt b/Documentation/devicetree/bindings/dma/fsl-imx-dma.txt
new file mode 100644
index 000000000000..2717ecb47db9
--- /dev/null
+++ b/Documentation/devicetree/bindings/dma/fsl-imx-dma.txt
@@ -0,0 +1,48 @@
+* Freescale Direct Memory Access (DMA) Controller for i.MX
+
+This document will only describe differences to the generic DMA Controller and
+DMA request bindings as described in dma/dma.txt .
+
+* DMA controller
+
+Required properties:
+- compatible : Should be "fsl,<chip>-dma". chip can be imx1, imx21 or imx27
+- reg : Should contain DMA registers location and length
+- interrupts : First item should be DMA interrupt, second one is optional and
+    should contain DMA Error interrupt
+- #dma-cells : Has to be 1. imx-dma does not support anything else.
+
+Optional properties:
+- #dma-channels : Number of DMA channels supported. Should be 16.
+- #dma-requests : Number of DMA requests supported.
+
+Example:
+
+        dma: dma@10001000 {
+                compatible = "fsl,imx27-dma";
+                reg = <0x10001000 0x1000>;
+                interrupts = <32 33>;
+                #dma-cells = <1>;
+                #dma-channels = <16>;
+        };
+
+
+* DMA client
+
+Clients have to specify the DMA requests with phandles in a list.
+
+Required properties:
+- dmas: List of one or more DMA request specifiers. One DMA request specifier
+    consists of a phandle to the DMA controller followed by the integer
+    specifiying the request line.
+- dma-names: List of string identifiers for the DMA requests. For the correct
+    names, have a look at the specific client driver.
+
+Example:
+
+        sdhci1: sdhci@10013000 {
+                ...
+                dmas = <&dma 7>;
+                dma-names = "rx-tx";
+                ...
+        };
diff --git a/drivers/dma/imx-dma.c b/drivers/dma/imx-dma.c
index f28583370d00..34c54cf08231 100644
--- a/drivers/dma/imx-dma.c
+++ b/drivers/dma/imx-dma.c
@@ -27,6 +27,8 @@
 #include <linux/clk.h>
 #include <linux/dmaengine.h>
 #include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/of_dma.h>
 
 #include <asm/irq.h>
 #include <linux/platform_data/dma-imx.h>
@@ -186,6 +188,11 @@ struct imxdma_engine {
         enum imx_dma_type               devtype;
 };
 
+struct imxdma_filter_data {
+        struct imxdma_engine    *imxdma;
+        int                      request;
+};
+
 static struct platform_device_id imx_dma_devtype[] = {
         {
                 .name = "imx1-dma",
@@ -202,6 +209,22 @@ static struct platform_device_id imx_dma_devtype[] = {
 };
 MODULE_DEVICE_TABLE(platform, imx_dma_devtype);
 
+static const struct of_device_id imx_dma_of_dev_id[] = {
+        {
+                .compatible = "fsl,imx1-dma",
+                .data = &imx_dma_devtype[IMX1_DMA],
+        }, {
+                .compatible = "fsl,imx21-dma",
+                .data = &imx_dma_devtype[IMX21_DMA],
+        }, {
+                .compatible = "fsl,imx27-dma",
+                .data = &imx_dma_devtype[IMX27_DMA],
+        }, {
+                /* sentinel */
+        }
+};
+MODULE_DEVICE_TABLE(of, imx_dma_of_dev_id);
+
 static inline int is_imx1_dma(struct imxdma_engine *imxdma)
 {
         return imxdma->devtype == IMX1_DMA;
@@ -996,13 +1019,50 @@ static void imxdma_issue_pending(struct dma_chan *chan)
         spin_unlock_irqrestore(&imxdma->lock, flags);
 }
 
+static bool imxdma_filter_fn(struct dma_chan *chan, void *param)
+{
+        struct imxdma_filter_data *fdata = param;
+        struct imxdma_channel *imxdma_chan = to_imxdma_chan(chan);
+
+        if (chan->device->dev != fdata->imxdma->dev)
+                return false;
+
+        imxdma_chan->dma_request = fdata->request;
+        chan->private = NULL;
+
+        return true;
+}
+
+static struct dma_chan *imxdma_xlate(struct of_phandle_args *dma_spec,
+                                                struct of_dma *ofdma)
+{
+        int count = dma_spec->args_count;
+        struct imxdma_engine *imxdma = ofdma->of_dma_data;
+        struct imxdma_filter_data fdata = {
+                .imxdma = imxdma,
+        };
+
+        if (count != 1)
+                return NULL;
+
+        fdata.request = dma_spec->args[0];
+
+        return dma_request_channel(imxdma->dma_device.cap_mask,
+                                        imxdma_filter_fn, &fdata);
+}
+
 static int __init imxdma_probe(struct platform_device *pdev)
         {
         struct imxdma_engine *imxdma;
         struct resource *res;
+        const struct of_device_id *of_id;
         int ret, i;
         int irq, irq_err;
 
+        of_id = of_match_device(imx_dma_of_dev_id, &pdev->dev);
+        if (of_id)
+                pdev->id_entry = of_id->data;
+
         imxdma = devm_kzalloc(&pdev->dev, sizeof(*imxdma), GFP_KERNEL);
         if (!imxdma)
                 return -ENOMEM;
@@ -1136,8 +1196,19 @@ static int __init imxdma_probe(struct platform_device *pdev)
                 goto err;
         }
 
+        if (pdev->dev.of_node) {
+                ret = of_dma_controller_register(pdev->dev.of_node,
+                                imxdma_xlate, imxdma);
+                if (ret) {
+                        dev_err(&pdev->dev, "unable to register of_dma_controller\n");
+                        goto err_of_dma_controller;
+                }
+        }
+
         return 0;
 
+err_of_dma_controller:
+        dma_async_device_unregister(&imxdma->dma_device);
 err:
         clk_disable_unprepare(imxdma->dma_ipg);
         clk_disable_unprepare(imxdma->dma_ahb);
@@ -1150,6 +1221,9 @@ static int imxdma_remove(struct platform_device *pdev)
 
         dma_async_device_unregister(&imxdma->dma_device);
 
+        if (pdev->dev.of_node)
+                of_dma_controller_free(pdev->dev.of_node);
+
         clk_disable_unprepare(imxdma->dma_ipg);
         clk_disable_unprepare(imxdma->dma_ahb);
 
@@ -1159,6 +1233,7 @@ static int imxdma_remove(struct platform_device *pdev)
 static struct platform_driver imxdma_driver = {
         .driver         = {
                 .name   = "imx-dma",
+                .of_match_table = imx_dma_of_dev_id,
         },
         .id_table       = imx_dma_devtype,
         .remove         = imxdma_remove,
diff --git a/include/linux/platform_data/dma-imx.h b/include/linux/platform_data/dma-imx.h
index f6d30cc1cb77..beac6b8b6a7b 100644
--- a/include/linux/platform_data/dma-imx.h
+++ b/include/linux/platform_data/dma-imx.h
@@ -60,10 +60,8 @@ static inline int imx_dma_is_ipu(struct dma_chan *chan)
 
 static inline int imx_dma_is_general_purpose(struct dma_chan *chan)
 {
-        return strstr(dev_name(chan->device->dev), "sdma") ||
-                !strcmp(dev_name(chan->device->dev), "imx1-dma") ||
-                !strcmp(dev_name(chan->device->dev), "imx21-dma") ||
-                !strcmp(dev_name(chan->device->dev), "imx27-dma");
+        return !strcmp(chan->device->dev->driver->name, "imx-sdma") ||
+                !strcmp(chan->device->dev->driver->name, "imx-dma");
 }
 
 #endif