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
|
From a1e9cfcbdb2182c6b9ee86403f2000907ff56d26 Mon Sep 17 00:00:00 2001
From: wavelet2 <20504977+wavelet2@users.noreply.github.com>
Date: Mon, 15 Apr 2019 10:00:20 +0100
Subject: [PATCH 426/773] Maxim MAX98357A I2S DAC overlay (#2935)
Add overlay for Maxim MAX98357A I2S DAC.
Signed-off-by: Richard Steedman <richard.steedman@gmail.com>
---
arch/arm/boot/dts/overlays/Makefile | 1 +
arch/arm/boot/dts/overlays/README | 9 ++
.../boot/dts/overlays/max98357a-overlay.dts | 84 +++++++++++++++++++
3 files changed, 94 insertions(+)
create mode 100644 arch/arm/boot/dts/overlays/max98357a-overlay.dts
--- a/arch/arm/boot/dts/overlays/Makefile
+++ b/arch/arm/boot/dts/overlays/Makefile
@@ -75,6 +75,7 @@ dtbo-$(CONFIG_ARCH_BCM2835) += \
justboom-dac.dtbo \
justboom-digi.dtbo \
ltc294x.dtbo \
+ max98357a.dtbo \
mbed-dac.dtbo \
mcp23017.dtbo \
mcp23s17.dtbo \
--- a/arch/arm/boot/dts/overlays/README
+++ b/arch/arm/boot/dts/overlays/README
@@ -1276,6 +1276,15 @@ Params: ltc2941 Select t
See the datasheet for more information.
+Name: max98357a
+Info: Configures the Maxim MAX98357A I2S DAC
+Load: dtoverlay=max98357a,<param>=<val>
+Params: no-sdmode Driver does not manage the state of the DAC's
+ SD_MODE pin (i.e. chip is always on).
+ sdmode-pin integer, GPIO pin connected to the SD_MODE input
+ of the DAC (default GPIO4 if parameter omitted).
+
+
Name: mbed-dac
Info: Configures the mbed AudioCODEC (TLV320AIC23B)
Load: dtoverlay=mbed-dac
--- /dev/null
+++ b/arch/arm/boot/dts/overlays/max98357a-overlay.dts
@@ -0,0 +1,84 @@
+// Overlay for Maxim MAX98357A audio DAC
+
+// dtparams:
+// no-sdmode - SD_MODE pin not managed by driver.
+// sdmode-pin - Specify GPIO pin to which SD_MODE is connected (default 4).
+
+/dts-v1/;
+/plugin/;
+
+/ {
+ compatible = "brcm,bcm2835", "brcm,bcm2708", "brcm,bcm2709";
+
+ /* Enable I2S */
+ fragment@0 {
+ target = <&i2s>;
+ __overlay__ {
+ status = "okay";
+ };
+ };
+
+ /* DAC whose SD_MODE pin is managed by driver (via GPIO pin) */
+ fragment@1 {
+ target-path = "/";
+ __overlay__ {
+ max98357a_dac: max98357a {
+ compatible = "maxim,max98357a";
+ #sound-dai-cells = <0>;
+ sdmode-gpios = <&gpio 4 0>; /* 2nd word overwritten by sdmode-pin parameter */
+ status = "okay";
+ };
+ };
+ };
+
+ /* DAC whose SD_MODE pin is not managed by driver */
+ fragment@2 {
+ target-path = "/";
+ __dormant__ {
+ max98357a_nsd: max98357a {
+ compatible = "maxim,max98357a";
+ #sound-dai-cells = <0>;
+ status = "okay";
+ };
+ };
+ };
+
+ /* Soundcard connecting I2S to DAC with SD_MODE */
+ fragment@3 {
+ target = <&sound>;
+ __overlay__ {
+ compatible = "simple-audio-card";
+ simple-audio-card,format = "i2s";
+ simple-audio-card,name = "MAX98357A";
+ status = "okay";
+ simple-audio-card,cpu {
+ sound-dai = <&i2s>;
+ };
+ simple-audio-card,codec {
+ sound-dai = <&max98357a_dac>;
+ };
+ };
+ };
+
+ /* Soundcard connecting I2S to DAC without SD_MODE */
+ fragment@4 {
+ target = <&sound>;
+ __dormant__ {
+ compatible = "simple-audio-card";
+ simple-audio-card,format = "i2s";
+ simple-audio-card,name = "MAX98357A";
+ status = "okay";
+ simple-audio-card,cpu {
+ sound-dai = <&i2s>;
+ };
+ simple-audio-card,codec {
+ sound-dai = <&max98357a_nsd>;
+ };
+ };
+ };
+
+ __overrides__ {
+ no-sdmode = <0>,"-1+2-3+4";
+ sdmode-pin = <&max98357a_dac>,"sdmode-gpios:4";
+ };
+};
|
