[PATCH] dmaengine: dw_dma: add Device Tree probing capability

[Viresh Kumar]

SPEAr platforms now support DT and so must convert all drivers to support DT.
This patch adds DT probing support for Synopsys DMA controller and updates its
documentation too.

Signed-off-by: Viresh Kumar <viresh.kumar at st.com>
---
 Documentation/devicetree/bindings/dma/snps-dma.txt |   17 +++++++++++++++++
 drivers/dma/dw_dmac.c                              |   10 ++++++++++
 2 files changed, 27 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/dma/snps-dma.txt

diff --git a/Documentation/devicetree/bindings/dma/snps-dma.txt b/Documentation/devicetree/bindings/dma/snps-dma.txt
new file mode 100644
index 0000000..c0d85db
--- /dev/null
+++ b/Documentation/devicetree/bindings/dma/snps-dma.txt
@@ -0,0 +1,17 @@
+* Synopsys Designware DMA Controller
+
+Required properties:
+- compatible: "snps,dma-spear1340"
+- reg: Address range of the DMAC registers
+- interrupt-parent: Should be the phandle for the interrupt controller
+  that services interrupts for this device
+- interrupt: Should contain the DMAC interrupt number
+
+Example:
+
+	dma at fc000000 {
+		compatible = "snps,dma-spear1340";
+		reg = <0xfc000000 0x1000>;
+		interrupt-parent = <&vic1>;
+		interrupts = <12>;
+	};
diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c
index 300d976..13b9298 100644
--- a/drivers/dma/dw_dmac.c
+++ b/drivers/dma/dw_dmac.c
@@ -17,6 +17,7 @@
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
+#include <linux/of.h>
 #include <linux/mm.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
@@ -1592,12 +1593,21 @@ static const struct dev_pm_ops dw_dev_pm_ops = {
 	.poweroff_noirq = dw_suspend_noirq,
 };
 
+#ifdef CONFIG_OF
+static const struct of_device_id dw_dma_id_table[] = {
+	{ .compatible = "snps,dma-spear1340" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, dw_dma_id_table);
+#endif
+
 static struct platform_driver dw_driver = {
 	.remove		= __exit_p(dw_remove),
 	.shutdown	= dw_shutdown,
 	.driver = {
 		.name	= "dw_dmac",
 		.pm	= &dw_dev_pm_ops,
+		.of_match_table = of_match_ptr(dw_dma_id_table),
 	},
 };
 
-- 
1.7.9