dma: mxs-dma: add device tree probe support

Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Rob Landley <rob@landley.net>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Huang Shijie <b32955@freescale.com>
Signed-off-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Marek Vasut <marex@denx.de>
Acked-by: Vinod Koul <vinod.koul@intel.com>

Documentation/devicetree/bindings/dma/fsl-mxs-dma.txt

@@ -0,0 +1,19 @@
+* Freescale MXS DMA
+
+Required properties:
+- compatible : Should be "fsl,<chip>-dma-apbh" or "fsl,<chip>-dma-apbx"
+- reg : Should contain registers location and length
+
+Supported chips:
+imx23, imx28.
+
+Examples:
+dma-apbh@80004000 {
+	compatible = "fsl,imx28-dma-apbh";
+	reg = <0x80004000 2000>;
+};
+
+dma-apbx@80024000 {
+	compatible = "fsl,imx28-dma-apbx";
+	reg = <0x80024000 2000>;
+};

drivers/dma/mxs-dma.c

@@ -22,8 +22,11 @@
 #include <linux/platform_device.h>
 #include <linux/dmaengine.h>
 #include <linux/delay.h>
+#include <linux/module.h>
 #include <linux/fsl/mxs-dma.h>
 #include <linux/stmp_device.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
 
 #include <asm/irq.h>
 #include <mach/mxs.h>
@@ -177,6 +180,15 @@ static struct platform_device_id mxs_dma_ids[] = {
 	}
 };
 
+static const struct of_device_id mxs_dma_dt_ids[] = {
+	{ .compatible = "fsl,imx23-dma-apbh", .data = &mxs_dma_ids[0], },
+	{ .compatible = "fsl,imx23-dma-apbx", .data = &mxs_dma_ids[1], },
+	{ .compatible = "fsl,imx28-dma-apbh", .data = &mxs_dma_ids[2], },
+	{ .compatible = "fsl,imx28-dma-apbx", .data = &mxs_dma_ids[3], },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mxs_dma_dt_ids);
+
 static struct mxs_dma_chan *to_mxs_dma_chan(struct dma_chan *chan)
 {
 	return container_of(chan, struct mxs_dma_chan, chan);
@@ -652,10 +664,9 @@ err_out:
 
 static int __init mxs_dma_probe(struct platform_device *pdev)
 {
-	const struct platform_device_id *id_entry =
-				platform_get_device_id(pdev);
-	const struct mxs_dma_type *dma_type =
-			(struct mxs_dma_type *)id_entry->driver_data;
+	const struct platform_device_id *id_entry;
+	const struct of_device_id *of_id;
+	const struct mxs_dma_type *dma_type;
 	struct mxs_dma_engine *mxs_dma;
 	struct resource *iores;
 	int ret, i;
@@ -664,8 +675,15 @@ static int __init mxs_dma_probe(struct platform_device *pdev)
 	if (!mxs_dma)
 		return -ENOMEM;
 
-	mxs_dma->dev_id = dma_type->id;
+	of_id = of_match_device(mxs_dma_dt_ids, &pdev->dev);
+	if (of_id)
+		id_entry = of_id->data;
+	else
+		id_entry = platform_get_device_id(pdev);
+
+	dma_type = (struct mxs_dma_type *)id_entry->driver_data;
 	mxs_dma->type = dma_type->type;
+	mxs_dma->dev_id = dma_type->id;
 
 	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 
@@ -751,6 +769,7 @@ err_request_region:
 static struct platform_driver mxs_dma_driver = {
 	.driver		= {
 		.name	= "mxs-dma",
+		.of_match_table = mxs_dma_dt_ids,
 	},
 	.id_table	= mxs_dma_ids,
 };