From e740bd2cc3fcd632fcd6c8881b1fc671bcde5914 Mon Sep 17 00:00:00 2001
From: dev-3Dlab <45081440+dev-3Dlab@users.noreply.github.com>
Date: Wed, 5 Dec 2018 10:59:11 +0100
Subject: [PATCH] ASoC: add driver for 3Dlab Nano soundcard (#2758)

Signed-off-by: GT <dev@3d-lab-av.com>
---
 .../overlays/3dlab-nano-player-overlay.dts    |  32 ++
 arch/arm/boot/dts/overlays/Makefile           |   1 +
 arch/arm/boot/dts/overlays/README             |   6 +
 sound/soc/bcm/3dlab-nano-player.c             | 370 ++++++++++++++++++
 sound/soc/bcm/Kconfig                         |   6 +
 sound/soc/bcm/Makefile                        |   2 +
 8 files changed, 419 insertions(+)
 create mode 100644 arch/arm/boot/dts/overlays/3dlab-nano-player-overlay.dts
 create mode 100644 sound/soc/bcm/3dlab-nano-player.c

--- /dev/null
+++ b/arch/arm/boot/dts/overlays/3dlab-nano-player-overlay.dts
@@ -0,0 +1,32 @@
+// Definitions for 3Dlab Nano Player
+/dts-v1/;
+/plugin/;
+
+/ {
+	compatible = "brcm,bcm2708";
+
+	fragment@0 {
+		target = <&i2s>;
+		__overlay__ {
+			status = "okay";
+		};
+	};
+
+	fragment@1 {
+		target = <&i2c>;
+		__overlay__ {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			status = "okay";
+
+			nano-player@41 {
+				compatible = "3dlab,nano-player";
+				reg = <0x41>;
+				i2s-controller = <&i2s>;
+				status = "okay";
+			};
+		};
+	};
+};
+
+// EOF
--- a/arch/arm/boot/dts/overlays/Makefile
+++ b/arch/arm/boot/dts/overlays/Makefile
@@ -1,6 +1,7 @@
 # Overlays for the Raspberry Pi platform
 
 dtbo-$(CONFIG_ARCH_BCM2835) += \
+	3dlab-nano-player.dtbo \
 	adau1977-adc.dtbo \
 	adau7002-simple.dtbo \
 	ads1015.dtbo \
--- a/arch/arm/boot/dts/overlays/README
+++ b/arch/arm/boot/dts/overlays/README
@@ -199,6 +199,12 @@ Params:
         and the other i2c baudrate parameters.
 
 
+Name:   3dlab-nano-player
+Info:   Configures the 3Dlab Nano Player
+Load:   dtoverlay=3dlab-nano-player
+Params: <None>
+
+
 Name:   adau1977-adc
 Info:   Overlay for activation of ADAU1977 ADC codec over I2C for control
         and I2S for data.
--- /dev/null
+++ b/sound/soc/bcm/3dlab-nano-player.c
@@ -0,0 +1,370 @@
+/*
+ * 3Dlab Nano Player ALSA SoC Audio driver.
+ *
+ * Copyright (C) 2018 3Dlab.
+ *
+ * Author: GT <dev@3d-lab-av.com>
+ *
+ * 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 <linux/module.h>
+#include <linux/i2c.h>
+#include <sound/soc.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/control.h>
+
+#define NANO_ID		0x00
+#define NANO_VER	0x01
+#define NANO_CFG	0x02
+#define NANO_STATUS	0x03
+#define NANO_SPI_ADDR	0x04
+#define NANO_SPI_DATA	0x05
+
+#define NANO_ID_VAL	0x3D
+#define NANO_CFG_OFF	0x00
+#define NANO_CFG_MULT1	0
+#define NANO_CFG_MULT2	1
+#define NANO_CFG_MULT4	2
+#define NANO_CFG_MULT8	3
+#define NANO_CFG_MULT16	4
+#define NANO_CFG_CLK22	0
+#define NANO_CFG_CLK24	BIT(3)
+#define NANO_CFG_DSD	BIT(4)
+#define NANO_CFG_ENA	BIT(5)
+#define NANO_CFG_BLINK	BIT(6)
+#define NANO_STATUS_P1  BIT(0)
+#define NANO_STATUS_P2  BIT(1)
+#define NANO_STATUS_FLG BIT(2)
+#define NANO_STATUS_CLK BIT(3)
+#define NANO_SPI_READ	0
+#define NANO_SPI_WRITE	BIT(5)
+
+#define NANO_DAC_CTRL1	0x00
+#define NANO_DAC_CTRL2	0x01
+#define NANO_DAC_CTRL3	0x02
+#define NANO_DAC_LATT	0x03
+#define NANO_DAC_RATT	0x04
+
+#define NANO_CTRL2_VAL	0x22
+
+static int nano_player_spi_write(struct regmap *map,
+				 unsigned int reg, unsigned int val)
+{
+	/* indirect register access */
+	regmap_write(map, NANO_SPI_DATA, val);
+	regmap_write(map, NANO_SPI_ADDR, reg | NANO_SPI_WRITE);
+	return 0;
+}
+
+static int nano_player_ctrl_info(struct snd_kcontrol *kcontrol,
+				 struct snd_ctl_elem_info *uinfo)
+{
+	/* describe control element */
+	if (strstr(kcontrol->id.name, "Volume")) {
+		uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+		uinfo->count = 1;
+		uinfo->value.integer.min = 0;
+		uinfo->value.integer.max = 100;
+	} else {
+		uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
+		uinfo->count = 1;
+		uinfo->value.integer.min = 0;
+		uinfo->value.integer.max = 1;
+	}
+
+	return 0;
+}
+
+static int nano_player_ctrl_put(struct snd_kcontrol *kcontrol,
+				struct snd_ctl_elem_value *ucontrol)
+{
+	/* program control value to hardware */
+	struct snd_soc_card *card = snd_kcontrol_chip(kcontrol);
+	struct regmap *regmap = snd_soc_card_get_drvdata(card);
+
+	if (strstr(kcontrol->id.name, "Volume")) {
+		unsigned int vol = ucontrol->value.integer.value[0];
+		unsigned int att = 255 - (2 * (100 - vol));
+
+		nano_player_spi_write(regmap, NANO_DAC_LATT, att);
+		nano_player_spi_write(regmap, NANO_DAC_RATT, att);
+		kcontrol->private_value = vol;
+	} else {
+		unsigned int mute = ucontrol->value.integer.value[0];
+		unsigned int reg = NANO_CTRL2_VAL | mute;
+
+		nano_player_spi_write(regmap, NANO_DAC_CTRL2, reg);
+		kcontrol->private_value = mute;
+	}
+	return 0;
+}
+
+static int nano_player_ctrl_get(struct snd_kcontrol *kcontrol,
+				struct snd_ctl_elem_value *ucontrol)
+{
+	/* return last programmed value */
+	ucontrol->value.integer.value[0] = kcontrol->private_value;
+	return 0;
+}
+
+#define SOC_NANO_PLAYER_CTRL(xname) \
+{	.iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = (xname), \
+	.access = SNDRV_CTL_ELEM_ACCESS_READWRITE, \
+	.info = nano_player_ctrl_info, \
+	.put = nano_player_ctrl_put, \
+	.get = nano_player_ctrl_get }
+
+static const struct snd_kcontrol_new nano_player_controls[] = {
+	SOC_NANO_PLAYER_CTRL("Master Playback Volume"),
+	SOC_NANO_PLAYER_CTRL("Master Playback Switch"),
+};
+
+static const unsigned int nano_player_rates[] = {
+	44100, 48000, 88200, 96000, 176400, 192000, 352800, 384000,
+	705600, 768000 /* only possible with fast clocks */
+};
+
+static struct snd_pcm_hw_constraint_list nano_player_constraint_rates = {
+	.list	= nano_player_rates,
+	.count	= ARRAY_SIZE(nano_player_rates),
+};
+
+static int nano_player_init(struct snd_soc_pcm_runtime *rtd)
+{
+	struct snd_soc_card *card = rtd->card;
+	struct regmap *regmap = snd_soc_card_get_drvdata(card);
+	struct snd_soc_pcm_stream *cpu = &rtd->cpu_dai->driver->playback;
+	struct snd_soc_pcm_stream *codec = &rtd->codec_dai->driver->playback;
+	unsigned int sample_bits = 32;
+	unsigned int val;
+
+	/* configure cpu dai */
+	cpu->formats |= SNDRV_PCM_FMTBIT_DSD_U32_LE;
+	cpu->rate_max = 768000;
+
+	/* configure dummy codec dai */
+	codec->rate_min = 44100;
+	codec->rates = SNDRV_PCM_RATE_KNOT;
+	codec->formats = SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_DSD_U32_LE;
+
+	/* configure max supported rate */
+	regmap_read(regmap, NANO_STATUS, &val);
+	if (val & NANO_STATUS_CLK) {
+		dev_notice(card->dev, "Board with fast clocks installed\n");
+		codec->rate_max = 768000;
+	} else {
+		dev_notice(card->dev, "Board with normal clocks installed\n");
+		codec->rate_max = 384000;
+	}
+
+	/* frame length enforced by hardware */
+	return snd_soc_dai_set_bclk_ratio(rtd->cpu_dai, sample_bits * 2);
+}
+
+static int nano_player_startup(struct snd_pcm_substream *substream)
+{
+	return snd_pcm_hw_constraint_list(substream->runtime, 0,
+					  SNDRV_PCM_HW_PARAM_RATE,
+					  &nano_player_constraint_rates);
+}
+
+static int nano_player_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_card *card = rtd->card;
+	struct regmap *regmap = snd_soc_card_get_drvdata(card);
+	unsigned int config = NANO_CFG_ENA;
+	struct snd_mask *fmt;
+
+	/* configure PCM or DSD */
+	fmt = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
+	if (snd_mask_test(fmt, SNDRV_PCM_FORMAT_DSD_U32_LE)) {
+		/* embed DSD in PCM data */
+		snd_mask_none(fmt);
+		snd_mask_set(fmt, SNDRV_PCM_FORMAT_S32_LE);
+		/* enable DSD mode */
+		config |= NANO_CFG_DSD;
+	}
+
+	/* configure clocks */
+	switch (params_rate(params)) {
+	case 44100:
+		config |= NANO_CFG_MULT1 | NANO_CFG_CLK22;
+		break;
+	case 88200:
+		config |= NANO_CFG_MULT2 | NANO_CFG_CLK22;
+		break;
+	case 176400:
+		config |= NANO_CFG_MULT4 | NANO_CFG_CLK22;
+		break;
+	case 352800:
+		config |= NANO_CFG_MULT8 | NANO_CFG_CLK22;
+		break;
+	case 705600:
+		config |= NANO_CFG_MULT16 | NANO_CFG_CLK22;
+		break;
+	case 48000:
+		config |= NANO_CFG_MULT1 | NANO_CFG_CLK24;
+		break;
+	case 96000:
+		config |= NANO_CFG_MULT2 | NANO_CFG_CLK24;
+		break;
+	case 192000:
+		config |= NANO_CFG_MULT4 | NANO_CFG_CLK24;
+		break;
+	case 384000:
+		config |= NANO_CFG_MULT8 | NANO_CFG_CLK24;
+		break;
+	case 768000:
+		config |= NANO_CFG_MULT16 | NANO_CFG_CLK24;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	dev_dbg(card->dev, "Send CFG register 0x%02X\n", config);
+	return regmap_write(regmap, NANO_CFG, config);
+}
+
+static struct snd_soc_ops nano_player_ops = {
+	.startup	= nano_player_startup,
+	.hw_params	= nano_player_hw_params,
+};
+
+static struct snd_soc_dai_link nano_player_link = {
+	.name		= "3Dlab Nano Player",
+	.stream_name	= "3Dlab Nano Player HiFi",
+	.platform_name	= "bcm2708-i2s.0",
+	.cpu_dai_name	= "bcm2708-i2s.0",
+	.codec_name	= "snd-soc-dummy",
+	.codec_dai_name	= "snd-soc-dummy-dai",
+	.dai_fmt	= SND_SOC_DAIFMT_I2S |
+			  SND_SOC_DAIFMT_CONT |
+			  SND_SOC_DAIFMT_NB_NF |
+			  SND_SOC_DAIFMT_CBM_CFM,
+	.init		= nano_player_init,
+	.ops		= &nano_player_ops,
+};
+
+static const struct regmap_config nano_player_regmap = {
+	.reg_bits	= 8,
+	.val_bits	= 8,
+	.max_register	= 128,
+	.cache_type	= REGCACHE_RBTREE,
+};
+
+static int nano_player_card_probe(struct snd_soc_card *card)
+{
+	struct regmap *regmap = snd_soc_card_get_drvdata(card);
+	unsigned int val;
+
+	/* check hardware integrity */
+	regmap_read(regmap, NANO_ID, &val);
+	if (val != NANO_ID_VAL) {
+		dev_err(card->dev, "Invalid ID register 0x%02X\n", val);
+		return -ENODEV;
+	}
+
+	/* report version to the user */
+	regmap_read(regmap, NANO_VER, &val);
+	dev_notice(card->dev, "Started 3Dlab Nano Player driver (v%d)\n", val);
+
+	/* enable internal audio bus and blink status LED */
+	return regmap_write(regmap, NANO_CFG, NANO_CFG_ENA | NANO_CFG_BLINK);
+}
+
+static int nano_player_card_remove(struct snd_soc_card *card)
+{
+	/* disable internal audio bus */
+	struct regmap *regmap = snd_soc_card_get_drvdata(card);
+
+	return regmap_write(regmap, NANO_CFG, NANO_CFG_OFF);
+}
+
+static struct snd_soc_card nano_player_card = {
+	.name		= "3Dlab_Nano_Player",
+	.owner		= THIS_MODULE,
+	.dai_link	= &nano_player_link,
+	.num_links	= 1,
+	.controls	= nano_player_controls,
+	.num_controls	= ARRAY_SIZE(nano_player_controls),
+	.probe		= nano_player_card_probe,
+	.remove		= nano_player_card_remove,
+};
+
+static int nano_player_i2c_probe(struct i2c_client *i2c,
+				 const struct i2c_device_id *id)
+{
+	struct regmap *regmap;
+	int ret;
+
+	regmap = devm_regmap_init_i2c(i2c, &nano_player_regmap);
+	if (IS_ERR(regmap)) {
+		ret = PTR_ERR(regmap);
+		dev_err(&i2c->dev, "Failed to init regmap %d\n", ret);
+		return ret;
+	}
+
+	if (i2c->dev.of_node) {
+		struct snd_soc_dai_link *dai = &nano_player_link;
+		struct device_node *node;
+
+		/* cpu handle configured by device tree */
+		node = of_parse_phandle(i2c->dev.of_node, "i2s-controller", 0);
+		if (node) {
+			dai->platform_name = NULL;
+			dai->platform_of_node = node;
+			dai->cpu_dai_name = NULL;
+			dai->cpu_of_node = node;
+		}
+	}
+
+	nano_player_card.dev = &i2c->dev;
+	snd_soc_card_set_drvdata(&nano_player_card, regmap);
+	ret = devm_snd_soc_register_card(&i2c->dev, &nano_player_card);
+
+	if (ret && ret != -EPROBE_DEFER)
+		dev_err(&i2c->dev, "Failed to register card %d\n", ret);
+
+	return ret;
+}
+
+static const struct of_device_id nano_player_of_match[] = {
+	{ .compatible = "3dlab,nano-player", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, nano_player_of_match);
+
+static const struct i2c_device_id nano_player_i2c_id[] = {
+	{ "nano-player", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, nano_player_i2c_id);
+
+static struct i2c_driver nano_player_i2c_driver = {
+	.probe		= nano_player_i2c_probe,
+	.id_table	= nano_player_i2c_id,
+	.driver		= {
+		.name		= "nano-player",
+		.owner		= THIS_MODULE,
+		.of_match_table	= nano_player_of_match,
+	},
+};
+
+module_i2c_driver(nano_player_i2c_driver);
+
+MODULE_DESCRIPTION("ASoC 3Dlab Nano Player driver");
+MODULE_AUTHOR("GT <dev@3d-lab-av.com>");
+MODULE_LICENSE("GPL v2");
+
+/* EOF */
--- a/sound/soc/bcm/Kconfig
+++ b/sound/soc/bcm/Kconfig
@@ -17,6 +17,12 @@ config SND_SOC_CYGNUS
 
 	  If you don't know what to do here, say N.
 
+config SND_BCM2708_SOC_3DLAB_NANO_PLAYER
+	tristate "Support for 3Dlab Nano Player"
+	depends on SND_BCM2708_SOC_I2S || SND_BCM2835_SOC_I2S
+	help
+	  Say Y or M if you want to add support for 3Dlab Nano Player.
+
 config SND_BCM2708_SOC_GOOGLEVOICEHAT_SOUNDCARD
 	tristate "Support for Google voiceHAT soundcard"
 	depends on SND_BCM2708_SOC_I2S || SND_BCM2835_SOC_I2S
--- a/sound/soc/bcm/Makefile
+++ b/sound/soc/bcm/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_SND_SOC_CYGNUS) += snd-soc-
 snd-soc-googlevoicehat-codec-objs := googlevoicehat-codec.o
 
 # BCM2708 Machine Support
+snd-soc-3dlab-nano-player-objs := 3dlab-nano-player.o
 snd-soc-hifiberry-dacplus-objs := hifiberry_dacplus.o
 snd-soc-justboom-dac-objs := justboom-dac.o
 snd-soc-rpi-cirrus-objs := rpi-cirrus.o
@@ -31,6 +32,7 @@ snd-soc-fe-pi-audio-objs := fe-pi-audio.
 snd-soc-rpi-simple-soundcard-objs := rpi-simple-soundcard.o
 snd-soc-rpi-wm8804-soundcard-objs := rpi-wm8804-soundcard.o
 
+obj-$(CONFIG_SND_BCM2708_SOC_3DLAB_NANO_PLAYER) += snd-soc-3dlab-nano-player.o
 obj-$(CONFIG_SND_BCM2708_SOC_GOOGLEVOICEHAT_SOUNDCARD)  += snd-soc-googlevoicehat-codec.o
 obj-$(CONFIG_SND_BCM2708_SOC_HIFIBERRY_DACPLUS) += snd-soc-hifiberry-dacplus.o
 obj-$(CONFIG_SND_BCM2708_SOC_JUSTBOOM_DAC) += snd-soc-justboom-dac.o
