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From f42cc245e1f3e586f1a26550e5760489b6c329ab Mon Sep 17 00:00:00 2001
From: Phil Elwell <phil@raspberrypi.org>
Date: Tue, 23 Jul 2019 12:55:07 +0100
Subject: [PATCH] overlays: audremap: Support GPIOs 18 & 19
PWM audio can also be used on GPIOs 18 and 19, so add the pins_18_19
parameter to select that location. pins_12_13 explicitly chooses GPIOs
12 and 13, although this is the default behaviour so is there only for
completeness.
See: https://github.com/raspberrypi/firmware/issues/1178
Signed-off-by: Phil Elwell <phil@raspberrypi.org>
---
arch/arm/boot/dts/overlays/README | 4 +++-
arch/arm/boot/dts/overlays/audremap-overlay.dts | 16 ++++++++++++++++
2 files changed, 19 insertions(+), 1 deletion(-)
--- a/arch/arm/boot/dts/overlays/README
+++ b/arch/arm/boot/dts/overlays/README
@@ -475,12 +475,14 @@ Params: <None>
Name: audremap
-Info: Switches PWM sound output to pins 12 (Right) & 13 (Left)
+Info: Switches PWM sound output to GPIOs on the 40-pin header
Load: dtoverlay=audremap,<param>=<val>
Params: swap_lr Reverse the channel allocation, which will also
swap the audio jack outputs (default off)
enable_jack Don't switch off the audio jack output
(default off)
+ pins_12_13 Select GPIOs 12 & 13 (default)
+ pins_18_19 Select GPIOs 18 & 19
Name: balena-fin
--- a/arch/arm/boot/dts/overlays/audremap-overlay.dts
+++ b/arch/arm/boot/dts/overlays/audremap-overlay.dts
@@ -7,13 +7,29 @@
fragment@0 {
target = <&audio_pins>;
frag0: __overlay__ {
+ };
+ };
+
+ fragment@1 {
+ target = <&audio_pins>;
+ __overlay__ {
brcm,pins = < 12 13 >;
brcm,function = < 4 >; /* alt0 alt0 */
};
};
+ fragment@2 {
+ target = <&audio_pins>;
+ __dormant__ {
+ brcm,pins = < 18 19 >;
+ brcm,function = < 2 >; /* alt5 alt5 */
+ };
+ };
+
__overrides__ {
swap_lr = <&frag0>, "swap_lr?";
enable_jack = <&frag0>, "enable_jack?";
+ pins_12_13 = <0>,"+1-2";
+ pins_18_19 = <0>,"-1+2";
};
};
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