1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
|
From 538f85c20d4209dbae6851f9733e3e3f0450ff32 Mon Sep 17 00:00:00 2001
From: Phil Elwell <phil@raspberrypi.org>
Date: Fri, 1 Jul 2016 22:34:52 +0100
Subject: [PATCH] BCM270X_DT: Overlay to re-enable HW CS on SPI0
See: https://github.com/raspberrypi/linux/issues/1547
Signed-off-by: Phil Elwell <phil@raspberrypi.org>
---
arch/arm/boot/dts/overlays/Makefile | 1 +
arch/arm/boot/dts/overlays/README | 6 ++++++
arch/arm/boot/dts/overlays/spi0-hw-cs-overlay.dts | 26 +++++++++++++++++++++++
3 files changed, 33 insertions(+)
create mode 100644 arch/arm/boot/dts/overlays/spi0-hw-cs-overlay.dts
--- a/arch/arm/boot/dts/overlays/Makefile
+++ b/arch/arm/boot/dts/overlays/Makefile
@@ -81,6 +81,7 @@ dtbo-$(RPI_DT_OVERLAYS) += smi-dev.dtbo
dtbo-$(RPI_DT_OVERLAYS) += smi-nand.dtbo
dtbo-$(RPI_DT_OVERLAYS) += spi-gpio35-39.dtbo
dtbo-$(RPI_DT_OVERLAYS) += spi-rtc.dtbo
+dtbo-$(RPI_DT_OVERLAYS) += spi0-hw-cs.dtbo
dtbo-$(RPI_DT_OVERLAYS) += spi1-1cs.dtbo
dtbo-$(RPI_DT_OVERLAYS) += spi1-2cs.dtbo
dtbo-$(RPI_DT_OVERLAYS) += spi1-3cs.dtbo
--- a/arch/arm/boot/dts/overlays/README
+++ b/arch/arm/boot/dts/overlays/README
@@ -1006,6 +1006,12 @@ Load: dtoverlay=spi-rtc,<param>=<val>
Params: pcf2123 Select the PCF2123 device
+Name: spi0-hw-cs
+Info: Re-enables hardware CS/CE (chip selects) for SPI0
+Load: dtoverlay=spi0-hw-cs
+Params: <None>
+
+
Name: spi1-1cs
Info: Enables spi1 with a single chip select (CS) line and associated spidev
dev node. The gpio pin number for the CS line and spidev device node
--- /dev/null
+++ b/arch/arm/boot/dts/overlays/spi0-hw-cs-overlay.dts
@@ -0,0 +1,26 @@
+/*
+ * Device tree overlay to re-enable hardware CS for SPI0
+ */
+
+/dts-v1/;
+/plugin/;
+
+/ {
+ compatible = "brcm,bcm2835", "brcm,bcm2836", "brcm,bcm2708", "brcm,bcm2709";
+
+ fragment@0 {
+ target = <&spi0>;
+ __overlay__ {
+ cs-gpios = <0>, <0>;
+ status = "okay";
+ };
+ };
+
+ fragment@1 {
+ target = <&spi0_cs_pins>;
+ __overlay__ {
+ brcm,pins = <8 7>;
+ brcm,function = <4>; /* alt0 */
+ };
+ };
+};
|
