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From 48eea36959fb8d854b4cf1ee4284646be5a279e0 Mon Sep 17 00:00:00 2001
From: Phil Elwell <phil@raspberrypi.org>
Date: Mon, 16 Jan 2017 14:53:12 +0000
Subject: [PATCH] BCM270X_DT: Add spi0-cs overlay
The spi0-cs overlay allows the software chip selectts to be modified
using the cs0_pin and cs1_pin parameters.
Signed-off-by: Phil Elwell <phil@raspberrypi.org>
---
arch/arm/boot/dts/overlays/Makefile | 1 +
arch/arm/boot/dts/overlays/README | 9 +++++++-
arch/arm/boot/dts/overlays/spi0-cs-overlay.dts | 29 ++++++++++++++++++++++++++
3 files changed, 38 insertions(+), 1 deletion(-)
create mode 100644 arch/arm/boot/dts/overlays/spi0-cs-overlay.dts
--- a/arch/arm/boot/dts/overlays/Makefile
+++ b/arch/arm/boot/dts/overlays/Makefile
@@ -83,6 +83,7 @@ dtbo-$(CONFIG_ARCH_BCM2835) += \
smi-nand.dtbo \
spi-gpio35-39.dtbo \
spi-rtc.dtbo \
+ spi0-cs.dtbo \
spi0-hw-cs.dtbo \
spi1-1cs.dtbo \
spi1-2cs.dtbo \
--- a/arch/arm/boot/dts/overlays/README
+++ b/arch/arm/boot/dts/overlays/README
@@ -1138,7 +1138,7 @@ Params: <None>
Name: spi-gpio35-39
-Info: move SPI function block to GPIO 35 to 39
+Info: Move SPI function block to GPIO 35 to 39
Load: dtoverlay=spi-gpio35-39
Params: <None>
@@ -1149,6 +1149,13 @@ Load: dtoverlay=spi-rtc,<param>=<val>
Params: pcf2123 Select the PCF2123 device
+Name: spi0-cs
+Info: Allows the (software) CS pins for SPI0 to be changed
+Load: dtoverlay=spi0-cs,<param>=<val>
+Params: cs0_pin GPIO pin for CS0 (default 8)
+ cs1_pin GPIO pin for CS1 (default 7)
+
+
Name: spi0-hw-cs
Info: Re-enables hardware CS/CE (chip selects) for SPI0
Load: dtoverlay=spi0-hw-cs
--- /dev/null
+++ b/arch/arm/boot/dts/overlays/spi0-cs-overlay.dts
@@ -0,0 +1,29 @@
+/dts-v1/;
+/plugin/;
+
+
+/ {
+ compatible = "brcm,bcm2835", "brcm,bcm2708", "brcm,bcm2709";
+
+ fragment@0 {
+ target = <&spi0_cs_pins>;
+ frag0: __overlay__ {
+ brcm,pins = <8 7>;
+ };
+ };
+
+ fragment@1 {
+ target = <&spi0>;
+ frag1: __overlay__ {
+ cs-gpios = <&gpio 8 1>, <&gpio 7 1>;
+ status = "okay";
+ };
+ };
+
+ __overrides__ {
+ cs0_pin = <&frag0>,"brcm,pins:0",
+ <&frag1>,"cs-gpios:4";
+ cs1_pin = <&frag0>,"brcm,pins:4",
+ <&frag1>,"cs-gpios:16";
+ };
+};
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