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diff --git a/target/linux/brcm2708/patches-4.4/0324-Allow-up-to-24dB-digital-gain-to-be-applied-when-usi.patch b/target/linux/brcm2708/patches-4.4/0324-Allow-up-to-24dB-digital-gain-to-be-applied-when-usi.patch
new file mode 100644
index 0000000000..ad4d3b1b96
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+++ b/target/linux/brcm2708/patches-4.4/0324-Allow-up-to-24dB-digital-gain-to-be-applied-when-usi.patch
@@ -0,0 +1,60 @@
+From d81de2a4a1223296b17dac8e652b0b31911f6dd1 Mon Sep 17 00:00:00 2001
+From: DigitalDreamtime <clive.messer@digitaldreamtime.co.uk>
+Date: Fri, 6 May 2016 09:42:55 +0100
+Subject: [PATCH 324/423] Allow up to 24dB digital gain to be applied when
+ using IQAudIO DAC
+
+24db_digital_gain DT param can be used to specify that PCM512x
+codec "Digital" volume control should not be limited to 0dB gain,
+and if specified will allow the full 24dB gain.
+
+Signed-off-by: DigitalDreamtime <clive.messer@digitaldreamtime.co.uk>
+---
+ arch/arm/boot/dts/overlays/README | 17 +++++++++++++++--
+ arch/arm/boot/dts/overlays/iqaudio-dac-overlay.dts | 6 +++++-
+ 2 files changed, 20 insertions(+), 3 deletions(-)
+
+--- a/arch/arm/boot/dts/overlays/README
++++ b/arch/arm/boot/dts/overlays/README
+@@ -490,8 +490,21 @@ Params: <None>
+
+ Name: iqaudio-dac
+ Info: Configures the IQaudio DAC audio card
+-Load: dtoverlay=iqaudio-dac
+-Params: <None>
++Load: dtoverlay=iqaudio-dac,<param>
++Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
++ Digital volume control. Enable with
++ "dtoverlay=iqaudio-dac,24db_digital_gain"
++ (The default behaviour is that the Digital
++ volume control is limited to a maximum of
++ 0dB. ie. it can attenuate but not provide
++ gain. For most users, this will be desired
++ as it will prevent clipping. By appending
++ the 24db_digital_gain parameter, the Digital
++ volume control will allow up to 24dB of
++ gain. If this parameter is enabled, it is the
++ responsibility of the user to ensure that
++ the Digital volume control is set to a value
++ that does not result in clipping/distortion!)
+
+
+ Name: iqaudio-dacplus
+--- a/arch/arm/boot/dts/overlays/iqaudio-dac-overlay.dts
++++ b/arch/arm/boot/dts/overlays/iqaudio-dac-overlay.dts
+@@ -30,10 +30,14 @@
+
+ fragment@2 {
+ target = <&sound>;
+- __overlay__ {
++ frag2: __overlay__ {
+ compatible = "iqaudio,iqaudio-dac";
+ i2s-controller = <&i2s>;
+ status = "okay";
+ };
+ };
++
++ __overrides__ {
++ 24db_digital_gain = <&frag2>,"iqaudio,24db_digital_gain?";
++ };
+ };