diff --git a/arch/arm/boot/dts/overlays/Makefile b/arch/arm/boot/dts/overlays/Makefile
index c04a64724583eb..cd4429606241fc 100644
--- a/arch/arm/boot/dts/overlays/Makefile
+++ b/arch/arm/boot/dts/overlays/Makefile
@@ -16,6 +16,7 @@ dtbo-$(RPI_DT_OVERLAYS) += adau1977-adc.dtbo
dtbo-$(RPI_DT_OVERLAYS) += ads1015.dtbo
dtbo-$(RPI_DT_OVERLAYS) += ads7846.dtbo
dtbo-$(RPI_DT_OVERLAYS) += akkordion-iqdacplus.dtbo
+dtbo-$(RPI_DT_OVERLAYS) += allo-piano-dac-pcm512x-audio.dtbo
dtbo-$(RPI_DT_OVERLAYS) += at86rf233.dtbo
dtbo-$(RPI_DT_OVERLAYS) += audioinjector-wm8731-audio.dtbo
dtbo-$(RPI_DT_OVERLAYS) += audremap.dtbo
diff --git a/arch/arm/boot/dts/overlays/README b/arch/arm/boot/dts/overlays/README
index 7401b2834228d3..df2734edc03b59 100644
--- a/arch/arm/boot/dts/overlays/README
+++ b/arch/arm/boot/dts/overlays/README
@@ -235,6 +235,26 @@ Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
that does not result in clipping/distortion!)
+Name: allo-piano-dac-pcm512x-audio
+Info: Configures the Allo Piano DAC (2.0/2.1) audio cards.
+ (NB. This initial support is for 2.0 channel audio ONLY! ie. stereo.
+ The subwoofer outputs on the Piano 2.1 are not currently supported!)
+Load: dtoverlay=allo-piano-dac-pcm512x-audio,
+Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
+ Digital volume control.
+ (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: at86rf233
Info: Configures the Atmel AT86RF233 802.15.4 low-power WPAN transceiver,
connected to spi0.0
diff --git a/arch/arm/boot/dts/overlays/allo-piano-dac-pcm512x-audio-overlay.dts b/arch/arm/boot/dts/overlays/allo-piano-dac-pcm512x-audio-overlay.dts
new file mode 100644
index 00000000000000..a5468d850a911c
--- /dev/null
+++ b/arch/arm/boot/dts/overlays/allo-piano-dac-pcm512x-audio-overlay.dts
@@ -0,0 +1,54 @@
+/*
+ * Definitions for Allo Piano DAC (2.0/2.1) boards
+ *
+ * NB. The Piano DAC 2.1 board contains 2x TI PCM5142 DAC's. One DAC is stereo
+ * (left/right) and the other provides a subwoofer output, using DSP on the
+ * chip for digital high/low pass crossover.
+ * The initial support for this hardware, that doesn't require any codec driver
+ * modifications, uses only one DAC chip for stereo (left/right) output, the
+ * chip with 0x4c slave address. The other chip at 0x4d is currently ignored!
+ */
+
+/dts-v1/;
+/plugin/;
+
+/ {
+ compatible = "brcm,bcm2708";
+
+ fragment@0 {
+ target = <&i2s>;
+ __overlay__ {
+ status = "okay";
+ };
+ };
+
+ fragment@1 {
+ target = <&i2c1>;
+ __overlay__ {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "okay";
+
+ pcm5142@4c {
+ #sound-dai-cells = <0>;
+ compatible = "ti,pcm5142";
+ reg = <0x4c>;
+ status = "okay";
+ };
+ };
+ };
+
+ fragment@2 {
+ target = <&sound>;
+ piano_dac: __overlay__ {
+ compatible = "allo,piano-dac";
+ i2s-controller = <&i2s>;
+ status = "okay";
+ };
+ };
+
+ __overrides__ {
+ 24db_digital_gain =
+ <&piano_dac>,"allo,24db_digital_gain?";
+ };
+};
diff --git a/arch/arm/configs/bcm2709_defconfig b/arch/arm/configs/bcm2709_defconfig
index cfb856e8bebc60..af169da179deda 100644
--- a/arch/arm/configs/bcm2709_defconfig
+++ b/arch/arm/configs/bcm2709_defconfig
@@ -879,6 +879,7 @@ CONFIG_SND_BCM2708_SOC_ADAU1977_ADC=m
CONFIG_SND_AUDIOINJECTOR_PI_SOUNDCARD=m
CONFIG_SND_DIGIDAC1_SOUNDCARD=m
CONFIG_SND_BCM2708_SOC_DIONAUDIO_LOCO=m
+CONFIG_SND_BCM2708_SOC_ALLO_PIANO_DAC=m
CONFIG_SND_SOC_ADAU1701=m
CONFIG_SND_SOC_WM8804_I2C=m
CONFIG_SND_SIMPLE_CARD=m
diff --git a/arch/arm/configs/bcmrpi_defconfig b/arch/arm/configs/bcmrpi_defconfig
index 2c92cfdb7d2247..b86fa88bee3ef8 100644
--- a/arch/arm/configs/bcmrpi_defconfig
+++ b/arch/arm/configs/bcmrpi_defconfig
@@ -871,6 +871,7 @@ CONFIG_SND_BCM2708_SOC_ADAU1977_ADC=m
CONFIG_SND_AUDIOINJECTOR_PI_SOUNDCARD=m
CONFIG_SND_DIGIDAC1_SOUNDCARD=m
CONFIG_SND_BCM2708_SOC_DIONAUDIO_LOCO=m
+CONFIG_SND_BCM2708_SOC_ALLO_PIANO_DAC=m
CONFIG_SND_SOC_ADAU1701=m
CONFIG_SND_SOC_WM8804_I2C=m
CONFIG_SND_SIMPLE_CARD=m
diff --git a/sound/soc/bcm/Kconfig b/sound/soc/bcm/Kconfig
index 8873fd8adce1d1..23eefb56fdc736 100644
--- a/sound/soc/bcm/Kconfig
+++ b/sound/soc/bcm/Kconfig
@@ -114,3 +114,10 @@ config SND_BCM2708_SOC_DIONAUDIO_LOCO
select SND_SOC_PCM5102a
help
Say Y or M if you want to add support for Dion Audio LOCO.
+
+config SND_BCM2708_SOC_ALLO_PIANO_DAC
+ tristate "Support for Allo Piano DAC"
+ depends on SND_BCM2708_SOC_I2S || SND_BCM2835_SOC_I2S
+ select SND_SOC_PCM512x_I2C
+ help
+ Say Y or M if you want to add support for Allo Piano DAC.
diff --git a/sound/soc/bcm/Makefile b/sound/soc/bcm/Makefile
index 17f70f95132223..a2b642f10ee676 100644
--- a/sound/soc/bcm/Makefile
+++ b/sound/soc/bcm/Makefile
@@ -19,6 +19,7 @@ snd-soc-raspidac3-objs := raspidac3.o
snd-soc-audioinjector-pi-soundcard-objs := audioinjector-pi-soundcard.o
snd-soc-digidac1-soundcard-objs := digidac1-soundcard.o
snd-soc-dionaudio-loco-objs := dionaudio_loco.o
+snd-soc-allo-piano-dac-objs := allo-piano-dac.o
obj-$(CONFIG_SND_BCM2708_SOC_ADAU1977_ADC) += snd-soc-adau1977-adc.o
obj-$(CONFIG_SND_BCM2708_SOC_HIFIBERRY_DAC) += snd-soc-hifiberry-dac.o
@@ -35,3 +36,4 @@ obj-$(CONFIG_SND_BCM2708_SOC_RASPIDAC3) += snd-soc-raspidac3.o
obj-$(CONFIG_SND_AUDIOINJECTOR_PI_SOUNDCARD) += snd-soc-audioinjector-pi-soundcard.o
obj-$(CONFIG_SND_DIGIDAC1_SOUNDCARD) += snd-soc-digidac1-soundcard.o
obj-$(CONFIG_SND_BCM2708_SOC_DIONAUDIO_LOCO) += snd-soc-dionaudio-loco.o
+obj-$(CONFIG_SND_BCM2708_SOC_ALLO_PIANO_DAC) += snd-soc-allo-piano-dac.o
diff --git a/sound/soc/bcm/allo-piano-dac.c b/sound/soc/bcm/allo-piano-dac.c
new file mode 100644
index 00000000000000..8e8e62e5a36a27
--- /dev/null
+++ b/sound/soc/bcm/allo-piano-dac.c
@@ -0,0 +1,144 @@
+/*
+ * ALSA ASoC Machine Driver for Allo Piano DAC
+ *
+ * Author: Baswaraj K
+ * Copyright 2016
+ * based on code by Daniel Matuschek
+ * based on code by Florian Meier
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+
+#include
+#include
+
+#include
+#include
+#include
+#include
+
+static bool digital_gain_0db_limit = true;
+
+static int snd_allo_piano_dac_init(struct snd_soc_pcm_runtime *rtd)
+{
+ if (digital_gain_0db_limit) {
+ int ret;
+ struct snd_soc_card *card = rtd->card;
+
+ ret = snd_soc_limit_volume(card, "Digital Playback Volume",
+ 207);
+ if (ret < 0)
+ dev_warn(card->dev, "Failed to set volume limit: %d\n",
+ ret);
+ }
+
+ return 0;
+}
+
+static int snd_allo_piano_dac_hw_params(
+ struct snd_pcm_substream *substream, struct snd_pcm_hw_params *params)
+{
+ struct snd_soc_pcm_runtime *rtd = substream->private_data;
+ struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
+
+ unsigned int sample_bits =
+ snd_pcm_format_physical_width(params_format(params));
+
+ return snd_soc_dai_set_bclk_ratio(cpu_dai, sample_bits * 2);
+}
+
+/* machine stream operations */
+static struct snd_soc_ops snd_allo_piano_dac_ops = {
+ .hw_params = snd_allo_piano_dac_hw_params,
+};
+
+static struct snd_soc_dai_link snd_allo_piano_dac_dai[] = {
+{
+ .name = "Piano DAC",
+ .stream_name = "Piano DAC HiFi",
+ .cpu_dai_name = "bcm2708-i2s.0",
+ .codec_dai_name = "pcm512x-hifi",
+ .platform_name = "bcm2708-i2s.0",
+ .codec_name = "pcm512x.1-004c",
+ .dai_fmt = SND_SOC_DAIFMT_I2S |
+ SND_SOC_DAIFMT_NB_NF |
+ SND_SOC_DAIFMT_CBS_CFS,
+ .ops = &snd_allo_piano_dac_ops,
+ .init = snd_allo_piano_dac_init,
+},
+};
+
+/* audio machine driver */
+static struct snd_soc_card snd_allo_piano_dac = {
+ .name = "PianoDAC",
+ .owner = THIS_MODULE,
+ .dai_link = snd_allo_piano_dac_dai,
+ .num_links = ARRAY_SIZE(snd_allo_piano_dac_dai),
+};
+
+static int snd_allo_piano_dac_probe(struct platform_device *pdev)
+{
+ int ret = 0;
+
+ snd_allo_piano_dac.dev = &pdev->dev;
+
+ if (pdev->dev.of_node) {
+ struct device_node *i2s_node;
+ struct snd_soc_dai_link *dai;
+
+ dai = &snd_allo_piano_dac_dai[0];
+ i2s_node = of_parse_phandle(pdev->dev.of_node,
+ "i2s-controller", 0);
+
+ if (i2s_node) {
+ dai->cpu_dai_name = NULL;
+ dai->cpu_of_node = i2s_node;
+ dai->platform_name = NULL;
+ dai->platform_of_node = i2s_node;
+ }
+
+ digital_gain_0db_limit = !of_property_read_bool(
+ pdev->dev.of_node, "allo,24db_digital_gain");
+ }
+
+ ret = snd_soc_register_card(&snd_allo_piano_dac);
+ if (ret)
+ dev_err(&pdev->dev,
+ "snd_soc_register_card() failed: %d\n", ret);
+
+ return ret;
+}
+
+static int snd_allo_piano_dac_remove(struct platform_device *pdev)
+{
+ return snd_soc_unregister_card(&snd_allo_piano_dac);
+}
+
+static const struct of_device_id snd_allo_piano_dac_of_match[] = {
+ { .compatible = "allo,piano-dac", },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, snd_allo_piano_dac_of_match);
+
+static struct platform_driver snd_allo_piano_dac_driver = {
+ .driver = {
+ .name = "snd-allo-piano-dac",
+ .owner = THIS_MODULE,
+ .of_match_table = snd_allo_piano_dac_of_match,
+ },
+ .probe = snd_allo_piano_dac_probe,
+ .remove = snd_allo_piano_dac_remove,
+};
+
+module_platform_driver(snd_allo_piano_dac_driver);
+
+MODULE_AUTHOR("Baswaraj K ");
+MODULE_DESCRIPTION("ALSA ASoC Machine Driver for Allo Piano DAC");
+MODULE_LICENSE("GPL v2");