[PATCH 6/6] spi: atmel: add dt property for DMA configuration for sam9x5 and sam9n12

[Wenyou Yang]

Signed-off-by: Wenyou Yang <wenyou.yang at atmel.com>
---
 arch/arm/boot/dts/at91sam9n12.dtsi |    2 ++
 arch/arm/boot/dts/at91sam9x5.dtsi  |    4 +++
 drivers/spi/spi-atmel.c            |   55 +++++++++++++++++++++++++++++++++++-
 3 files changed, 60 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/at91sam9n12.dtsi b/arch/arm/boot/dts/at91sam9n12.dtsi
index c6868a2..b51f94d 100644
--- a/arch/arm/boot/dts/at91sam9n12.dtsi
+++ b/arch/arm/boot/dts/at91sam9n12.dtsi
@@ -98,6 +98,7 @@
 				compatible = "atmel,at91sam9g45-dma";
 				reg = <0xffffec00 0x200>;
 				interrupts = <20 4 0>;
+				#dma-cells = <1>;
 			};
 
 			pioA: gpio at fffff400 {
@@ -197,6 +198,7 @@
 				has_dma_support = <1>;
 				has_pdc_support = <0>;
 				is_ver2 = <1>;
+				dma = <&dma 0x10002212>;
 				status = "disabled";
 			};
 
diff --git a/arch/arm/boot/dts/at91sam9x5.dtsi b/arch/arm/boot/dts/at91sam9x5.dtsi
index f124473..ee46cb7 100644
--- a/arch/arm/boot/dts/at91sam9x5.dtsi
+++ b/arch/arm/boot/dts/at91sam9x5.dtsi
@@ -100,12 +100,14 @@
 				compatible = "atmel,at91sam9g45-dma";
 				reg = <0xffffec00 0x200>;
 				interrupts = <20 4 0>;
+				#dma-cells = <1>;
 			};
 
 			dma1: dma-controller at ffffee00 {
 				compatible = "atmel,at91sam9g45-dma";
 				reg = <0xffffee00 0x200>;
 				interrupts = <21 4 0>;
+				#dma-cells = <1>;
 			};
 
 			pioA: gpio at fffff400 {
@@ -248,6 +250,7 @@
 				has_dma_support = <1>;
 				has_pdc_support = <0>;
 				is_ver2 = <1>;
+				dma = <&dma0 0x10002212>;
 				status = "disabled";
 			};
 
@@ -265,6 +268,7 @@
 				has_dma_support = <1>;
 				has_pdc_support = <0>;
 				is_ver2 = <1>;
+				dma = <&dma1 0x10002212>;
 				status = "disabled";
 			};
 		};
diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 9930438..ad19423 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -1436,6 +1436,57 @@ static void atmel_spi_cleanup(struct spi_device *spi)
 	kfree(asd);
 }
 
+static int at91_spi_of_init(struct device_node *np,
+			struct at_dma_slave *atslave)
+{
+	struct of_phandle_args  dma_spec;
+	struct device_node      *dmac_np;
+	struct platform_device  *dmac_pdev;
+	const __be32            *nbcells;
+	int                     ret;
+
+	ret = of_parse_phandle_with_args(np, "dma", "#dma-cells", 0, &dma_spec);
+	if (ret || !dma_spec.np) {
+		pr_err("%s: can't parse dma property (%d)\n",
+						np->full_name, ret);
+		goto err0;
+	}
+	dmac_np = dma_spec.np;
+
+	/* check property format */
+	nbcells = of_get_property(dmac_np, "#dma-cells", NULL);
+	if (!nbcells) {
+		pr_err("%s: #dma-cells property is required\n", np->full_name);
+		ret = -EINVAL;
+		goto err1;
+	}
+
+	if (dma_spec.args_count != be32_to_cpup(nbcells)
+			|| dma_spec.args_count != 1) {
+		pr_err("%s: wrong #dma-cells for %s\n",
+				np->full_name, dmac_np->full_name);
+		ret = -EINVAL;
+		goto err1;
+	}
+
+	dmac_pdev = of_find_device_by_node(dmac_np);
+	if (!dmac_pdev) {
+		pr_err("%s: unable to find pdev from DMA controller\n",
+				dmac_np->full_name);
+		ret = -EINVAL;
+		goto err1;
+	}
+
+	atslave->dma_dev = &dmac_pdev->dev;
+	atslave->cfg = dma_spec.args[0];
+
+err1:
+	of_node_put(dma_spec.np);
+err0:
+	pr_debug("%s exited with status %d\n", __func__, ret);
+	return ret;
+}
+
 static int of_get_atmel_spi_data(struct device_node *np, struct atmel_spi *as)
 {
 	const __be32	*val;
@@ -1540,7 +1591,9 @@ static int __devinit atmel_spi_probe(struct platform_device *pdev)
 		goto out_unmap_regs;
 
 	if (as->data.has_dma_support) {
-		if (atmel_spi_configure_dma(as) == 0)
+		if ((at91_spi_of_init(pdev->dev.of_node,
+				&as->data.dma_slave) == 0)
+				&& (atmel_spi_configure_dma(as) == 0))
 			as->use_dma = true;
 	} else if (as->data.has_pdc_support)
 		as->use_pdc = true;
-- 
1.7.9.5