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
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
|
From 2d787b8c422a777f688b185420268dc618d995e4 Mon Sep 17 00:00:00 2001
From: Dave Stevenson <6by9@users.noreply.github.com>
Date: Mon, 8 Feb 2016 23:49:41 +0000
Subject: [PATCH 161/304] DT: Add overlays to configure I2C pins
Lifted from
https://www.raspberrypi.org/forums/viewtopic.php?f=107&t=120938&p=825883
so not claiming this to be my own work.
Adds overlays i2c0-bcm2708 and i2c1-bcm2708 that allow the pin
allocations for i2c-0 and i2c-1 to be changed.
---
arch/arm/boot/dts/overlays/Makefile | 2 ++
arch/arm/boot/dts/overlays/README | 16 ++++++++++
.../arm/boot/dts/overlays/i2c0-bcm2708-overlay.dts | 36 +++++++++++++++++++++
.../arm/boot/dts/overlays/i2c1-bcm2708-overlay.dts | 37 ++++++++++++++++++++++
4 files changed, 91 insertions(+)
create mode 100644 arch/arm/boot/dts/overlays/i2c0-bcm2708-overlay.dts
create mode 100644 arch/arm/boot/dts/overlays/i2c1-bcm2708-overlay.dts
--- a/arch/arm/boot/dts/overlays/Makefile
+++ b/arch/arm/boot/dts/overlays/Makefile
@@ -29,6 +29,8 @@ dtb-$(RPI_DT_OVERLAYS) += hy28a-overlay.
dtb-$(RPI_DT_OVERLAYS) += hy28b-overlay.dtb
dtb-$(RPI_DT_OVERLAYS) += i2c-rtc-overlay.dtb
dtb-$(RPI_DT_OVERLAYS) += i2c-gpio-overlay.dtb
+dtb-$(RPI_DT_OVERLAYS) += i2c0-bcm2708-overlay.dtb
+dtb-$(RPI_DT_OVERLAYS) += i2c1-bcm2708-overlay.dtb
dtb-$(RPI_DT_OVERLAYS) += i2s-mmap-overlay.dtb
dtb-$(RPI_DT_OVERLAYS) += iqaudio-dac-overlay.dtb
dtb-$(RPI_DT_OVERLAYS) += iqaudio-dacplus-overlay.dtb
--- a/arch/arm/boot/dts/overlays/README
+++ b/arch/arm/boot/dts/overlays/README
@@ -371,6 +371,22 @@ Params: ds1307 Select t
pcf8563 Select the PCF8563 device
+Name: i2c0-bcm2708
+Info: Enable the i2c_bcm2708 driver for the i2c0 bus
+Load: dtoverlay=i2c0-bcm2708,<param>=<val>
+Params: sda0_pin GPIO pin for SDA0 (0, 28 [or 44] - default 0)
+ scl0_pin GPIO pin for SCL0 (1, 29 [or 45] - default 1)
+
+
+Name: i2c1-bcm2708
+Info: Enable the i2c_bcm2708 driver for the i2c1 bus
+Load: dtoverlay=i2c1-bcm2708,<param>=<val>
+Params: sda1_pin GPIO pin for SDA1 (2 or 44 - default 2)
+ scl1_pin GPIO pin for SCL1 (3 or 45 - default 3)
+ pin_func Alternative pin function (4 (alt0), 6 (alt2) -
+ default 4)
+
+
Name: i2s-mmap
Info: Enables mmap support in the bcm2708-i2s driver
Load: dtoverlay=i2s-mmap
--- /dev/null
+++ b/arch/arm/boot/dts/overlays/i2c0-bcm2708-overlay.dts
@@ -0,0 +1,36 @@
+/*
+ * Device tree overlay for i2c_bcm2708, i2c0 bus
+ *
+ * Compile:
+ * dtc -@ -I dts -O dtb -o i2c0-bcm2708-overlay.dtb i2c0-bcm2708-overlay.dts
+ */
+
+/dts-v1/;
+/plugin/;
+
+/{
+ compatible = "brcm,bcm2708";
+
+ fragment@0 {
+ target = <&i2c0>;
+ __overlay__ {
+ pinctrl-0 = <&i2c0_pins>;
+ status = "okay";
+ };
+ };
+
+ fragment@1 {
+ target = <&gpio>;
+ __overlay__ {
+ i2c0_pins: i2c0 {
+ brcm,pins = <0 1>;
+ brcm,function = <4>; /* alt0 */
+ };
+ };
+ };
+
+ __overrides__ {
+ sda0_pin = <&i2c0_pins>,"brcm,pins:0";
+ scl0_pin = <&i2c0_pins>,"brcm,pins:4";
+ };
+};
--- /dev/null
+++ b/arch/arm/boot/dts/overlays/i2c1-bcm2708-overlay.dts
@@ -0,0 +1,37 @@
+/*
+ * Device tree overlay for i2c_bcm2708, i2c1 bus
+ *
+ * Compile:
+ * dtc -@ -I dts -O dtb -o i2c1-bcm2708-overlay.dtb i2c1-bcm2708-overlay.dts
+ */
+
+/dts-v1/;
+/plugin/;
+
+/{
+ compatible = "brcm,bcm2708";
+
+ fragment@0 {
+ target = <&i2c1>;
+ __overlay__ {
+ pinctrl-0 = <&i2c1_pins>;
+ status = "okay";
+ };
+ };
+
+ fragment@1 {
+ target = <&gpio>;
+ __overlay__ {
+ i2c1_pins: i2c1 {
+ brcm,pins = <2 3>;
+ brcm,function = <4>; /* alt0 */
+ };
+ };
+ };
+
+ __overrides__ {
+ sda1_pin = <&i2c1_pins>,"brcm,pins:0";
+ scl1_pin = <&i2c1_pins>,"brcm,pins:4";
+ pin_func = <&i2c1_pins>,"brcm,function:0";
+ };
+};
|
