openwrt/target/linux/brcm2708/patches-4.1/0159-dt-overlay-to-enable-dma-for-spi-driver.patch

From bcbfa93c85c8d272a765b1db0ba3e35b917e5afd Mon Sep 17 00:00:00 2001
From: Martin Sperl <kernel@martin.sperl.org>
Date: Wed, 22 Jul 2015 08:34:41 +0000
Subject: [PATCH 159/222] dt-overlay to enable dma for spi driver

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
---
 arch/arm/boot/dts/overlays/Makefile            |  1 +
 arch/arm/boot/dts/overlays/spi-dma-overlay.dts | 20 ++++++++++++++++++++
 2 files changed, 21 insertions(+)
 create mode 100755 arch/arm/boot/dts/overlays/spi-dma-overlay.dts

--- a/arch/arm/boot/dts/overlays/Makefile
+++ b/arch/arm/boot/dts/overlays/Makefile
@@ -45,6 +45,7 @@ dtb-$(RPI_DT_OVERLAYS) += rpi-sense-over
 dtb-$(RPI_DT_OVERLAYS) += sdhost-overlay.dtb
 dtb-$(RPI_DT_OVERLAYS) += spi-bcm2708-overlay.dtb
 dtb-$(RPI_DT_OVERLAYS) += spi-bcm2835-overlay.dtb
+dtb-$(RPI_DT_OVERLAYS) += spi-dma-overlay.dtb
 dtb-$(RPI_DT_OVERLAYS) += tinylcd35-overlay.dtb
 dtb-$(RPI_DT_OVERLAYS) += uart1-overlay.dtb
 dtb-$(RPI_DT_OVERLAYS) += vga666-overlay.dtb
--- /dev/null
+++ b/arch/arm/boot/dts/overlays/spi-dma-overlay.dts
@@ -0,0 +1,20 @@
+/*
+ * Device tree overlay for spi-bcm2835 to allow dma
+ */
+
+/dts-v1/;
+/plugin/;
+
+/ {
+	compatible = "brcm,bcm2835", "brcm,bcm2836", "brcm,bcm2708", "brcm,bcm2709";
+
+	fragment@0 {
+		target = <&spi0>;
+		__overlay__ {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			dmas = <&dma 6>, <&dma 7>;
+			dma-names = "tx", "rx";
+		};
+	};
+ };