From 0fa0f5932fff8c960862176fd61a7bccd2f28b90 Mon Sep 17 00:00:00 2001
From: David Knell <david.knell@gmail.com>
Date: Wed, 28 Oct 2020 14:21:37 +0000
Subject: [PATCH] PiFi-40 driver, Makefile and Kconfig

Signed-off-by: David Knell <david.knell@gmail.com>
---
 sound/soc/bcm/Kconfig   |   8 ++
 sound/soc/bcm/Makefile  |   3 +
 sound/soc/bcm/pifi-40.c | 283 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 294 insertions(+)
 create mode 100644 sound/soc/bcm/pifi-40.c

--- a/sound/soc/bcm/Kconfig
+++ b/sound/soc/bcm/Kconfig
@@ -100,6 +100,14 @@ config SND_BCM2708_SOC_HIFIBERRY_AMP
         help
          Say Y or M if you want to add support for the HifiBerry Amp amplifier board.
 
+ config SND_BCM2708_SOC_PIFI_40
+         tristate "Support for the PiFi-40 amp"
+         depends on SND_BCM2708_SOC_I2S || SND_BCM2835_SOC_I2S
+         select SND_SOC_TAS571X
+         select SND_PIFI_40
+         help
+          Say Y or M if you want to add support for the PiFi40 amp board
+
 config SND_BCM2708_SOC_RPI_CIRRUS
         tristate "Support for Cirrus Logic Audio Card"
         depends on SND_BCM2708_SOC_I2S || SND_BCM2835_SOC_I2S
--- a/sound/soc/bcm/Makefile
+++ b/sound/soc/bcm/Makefile
@@ -45,6 +45,7 @@ snd-soc-pisound-objs := pisound.o
 snd-soc-fe-pi-audio-objs := fe-pi-audio.o
 snd-soc-rpi-simple-soundcard-objs := rpi-simple-soundcard.o
 snd-soc-rpi-wm8804-soundcard-objs := rpi-wm8804-soundcard.o
+snd-soc-pifi-40-objs := pifi-40.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
@@ -74,3 +75,5 @@ obj-$(CONFIG_SND_PISOUND) += snd-soc-pis
 obj-$(CONFIG_SND_BCM2708_SOC_FE_PI_AUDIO) += snd-soc-fe-pi-audio.o
 obj-$(CONFIG_SND_RPI_SIMPLE_SOUNDCARD) += snd-soc-rpi-simple-soundcard.o
 obj-$(CONFIG_SND_RPI_WM8804_SOUNDCARD) += snd-soc-rpi-wm8804-soundcard.o
+obj-$(CONFIG_SND_BCM2708_SOC_PIFI_40) += snd-soc-pifi-40.o
+
--- /dev/null
+++ b/sound/soc/bcm/pifi-40.c
@@ -0,0 +1,283 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ALSA ASoC Machine Driver for PiFi-40
+ *
+ * Author:	David Knell <david.knell@gmail.com)
+ *		based on code by Daniel Matuschek <info@crazy-audio.com>
+ *		based on code by Florian Meier <florian.meier@koalo.de>
+ * Copyright (C) 2020
+ *
+ * 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/platform_device.h>
+#include <linux/gpio/consumer.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <linux/firmware.h>
+#include <linux/delay.h>
+#include <sound/tlv.h>
+
+static struct gpio_desc *pdn_gpio;
+static int vol = 0x30;
+
+// Volume control
+static int pifi_40_vol_get(struct snd_kcontrol *kcontrol,
+			   struct snd_ctl_elem_value *ucontrol)
+{
+	ucontrol->value.integer.value[0] = vol;
+	ucontrol->value.integer.value[1] = vol;
+	return 0;
+}
+
+static int pifi_40_vol_set(struct snd_kcontrol *kcontrol,
+			   struct snd_ctl_elem_value *ucontrol)
+{
+	struct snd_soc_card *card = snd_kcontrol_chip(kcontrol);
+	struct snd_soc_pcm_runtime *rtd;
+	unsigned int v = ucontrol->value.integer.value[0];
+	struct snd_soc_component *dac[2];
+
+	rtd = snd_soc_get_pcm_runtime(card, &card->dai_link[0]);
+	dac[0] = asoc_rtd_to_codec(rtd, 0)->component;
+	dac[1] = asoc_rtd_to_codec(rtd, 1)->component;
+
+	snd_soc_component_write(dac[0], 0x07, 255 - v);
+	snd_soc_component_write(dac[1], 0x07, 255 - v);
+
+	vol = v;
+	return 1;
+}
+
+static const DECLARE_TLV_DB_SCALE(digital_tlv_master, -10350, 50, 1);
+static const struct snd_kcontrol_new pifi_40_controls[] = {
+	SOC_DOUBLE_R_EXT_TLV("Master Volume", 0x00, 0x01,
+			     0x00, // Min
+			     0xff, // Max
+			     0x01, // Invert
+			     pifi_40_vol_get, pifi_40_vol_set,
+			     digital_tlv_master)
+};
+
+static const char * const codec_ctl_pfx[] = { "Left", "Right" };
+
+static const char * const codec_ctl_name[] = { "Master Volume",
+					"Speaker Volume",
+					"Speaker Switch" };
+
+static int snd_pifi_40_init(struct snd_soc_pcm_runtime *rtd)
+{
+	struct snd_soc_card *card = rtd->card;
+	struct snd_soc_component *dac[2];
+	struct snd_kcontrol *kctl;
+	int i, j;
+
+	dac[0] = asoc_rtd_to_codec(rtd, 0)->component;
+	dac[1] = asoc_rtd_to_codec(rtd, 1)->component;
+
+
+	// Set up cards - pulse power down first
+	gpiod_set_value_cansleep(pdn_gpio, 1);
+	usleep_range(1000, 10000);
+	gpiod_set_value_cansleep(pdn_gpio, 0);
+	usleep_range(20000, 30000);
+
+	// Oscillator trim
+	snd_soc_component_write(dac[0], 0x1b, 0);
+	snd_soc_component_write(dac[1], 0x1b, 0);
+	usleep_range(60000, 80000);
+
+	// Common setup
+	for (i = 0; i < 2; i++) {
+		// MCLK at 64fs, sample rate 44.1 or 48kHz
+		snd_soc_component_write(dac[i], 0x00, 0x60);
+
+		// Set up for PBTL
+		snd_soc_component_write(dac[i], 0x19, 0x3A);
+		snd_soc_component_write(dac[i], 0x25, 0x01103245);
+
+		// Master vol to -10db
+		snd_soc_component_write(dac[i], 0x07, 0x44);
+	}
+	// Inputs set to L and R respectively
+	snd_soc_component_write(dac[0], 0x20, 0x00017772);
+	snd_soc_component_write(dac[1], 0x20, 0x00107772);
+
+	// Remove codec controls
+	for (i = 0; i < 2; i++) {
+		for (j = 0; j < 3; j++) {
+			char cname[256];
+
+			sprintf(cname, "%s %s", codec_ctl_pfx[i],
+				codec_ctl_name[j]);
+			kctl = snd_soc_card_get_kcontrol(card, cname);
+			if (!kctl) {
+				pr_info("Control %s not found\n",
+				       cname);
+			} else {
+				kctl->vd[0].access =
+					SNDRV_CTL_ELEM_ACCESS_READWRITE;
+				snd_ctl_remove(card->snd_card, kctl);
+			}
+		}
+	}
+
+	return 0;
+}
+
+static int snd_pifi_40_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 = asoc_rtd_to_cpu(rtd, 0);
+	unsigned int sample_bits;
+
+	sample_bits = snd_pcm_format_physical_width(params_format(params));
+	return snd_soc_dai_set_bclk_ratio(cpu_dai, 64);
+}
+
+static struct snd_soc_ops snd_pifi_40_ops = { .hw_params =
+						      snd_pifi_40_hw_params };
+
+static struct snd_soc_dai_link_component pifi_40_codecs[] = {
+	{
+		.dai_name = "tas571x-hifi",
+	},
+	{
+		.dai_name = "tas571x-hifi",
+	},
+};
+
+SND_SOC_DAILINK_DEFS(
+	pifi_40_dai, DAILINK_COMP_ARRAY(COMP_EMPTY()),
+	DAILINK_COMP_ARRAY(COMP_CODEC("tas571x.1-001a", "tas571x-hifi"),
+			   COMP_CODEC("tas571x.1-001b", "tas571x-hifi")),
+	DAILINK_COMP_ARRAY(COMP_EMPTY()));
+
+static struct snd_soc_dai_link snd_pifi_40_dai[] = {
+	{
+		.name = "PiFi40",
+		.stream_name = "PiFi40",
+		.dai_fmt = SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_NB_NF |
+			   SND_SOC_DAIFMT_CBS_CFS,
+		.ops = &snd_pifi_40_ops,
+		.init = snd_pifi_40_init,
+		SND_SOC_DAILINK_REG(pifi_40_dai),
+	},
+};
+
+// Machine driver
+static struct snd_soc_card snd_pifi_40 = {
+	.name = "PiFi40",
+	.owner = THIS_MODULE,
+	.dai_link = snd_pifi_40_dai,
+	.num_links = ARRAY_SIZE(snd_pifi_40_dai),
+	.controls = pifi_40_controls,
+	.num_controls = ARRAY_SIZE(pifi_40_controls)
+};
+
+static void snd_pifi_40_pdn(struct snd_soc_card *card, int on)
+{
+	if (pdn_gpio)
+		gpiod_set_value_cansleep(pdn_gpio, on ? 0 : 1);
+}
+
+static int snd_pifi_40_probe(struct platform_device *pdev)
+{
+	struct snd_soc_card *card = &snd_pifi_40;
+	int ret = 0, i = 0;
+
+	card->dev = &pdev->dev;
+	platform_set_drvdata(pdev, &snd_pifi_40);
+
+	if (pdev->dev.of_node) {
+		struct device_node *i2s_node;
+		struct snd_soc_dai_link *dai;
+
+		dai = &snd_pifi_40_dai[0];
+		i2s_node = of_parse_phandle(pdev->dev.of_node, "i2s-controller",
+					    0);
+		if (i2s_node) {
+			for (i = 0; i < card->num_links; i++) {
+				dai->cpus->dai_name = NULL;
+				dai->cpus->of_node = i2s_node;
+				dai->platforms->name = NULL;
+				dai->platforms->of_node = i2s_node;
+			}
+		}
+
+		pifi_40_codecs[0].of_node =
+			of_parse_phandle(pdev->dev.of_node, "audio-codec", 0);
+		pifi_40_codecs[1].of_node =
+			of_parse_phandle(pdev->dev.of_node, "audio-codec", 1);
+		if (!pifi_40_codecs[0].of_node || !pifi_40_codecs[1].of_node) {
+			dev_err(&pdev->dev,
+				"Property 'audio-codec' missing or invalid\n");
+			return -EINVAL;
+		}
+
+		pdn_gpio = devm_gpiod_get_optional(&pdev->dev, "pdn",
+						   GPIOD_OUT_LOW);
+		if (IS_ERR(pdn_gpio)) {
+			ret = PTR_ERR(pdn_gpio);
+			dev_err(&pdev->dev, "failed to get pdn gpio: %d\n",
+				ret);
+			return ret;
+		}
+
+		ret = snd_soc_register_card(&snd_pifi_40);
+		if (ret < 0) {
+			dev_err(&pdev->dev,
+				"snd_soc_register_card() failed: %d\n", ret);
+			return ret;
+		}
+
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static int snd_pifi_40_remove(struct platform_device *pdev)
+{
+	struct snd_soc_card *card = platform_get_drvdata(pdev);
+
+	kfree(&card->drvdata);
+	snd_pifi_40_pdn(&snd_pifi_40, 0);
+	return snd_soc_unregister_card(&snd_pifi_40);
+}
+
+static const struct of_device_id snd_pifi_40_of_match[] = {
+	{
+		.compatible = "pifi,pifi-40",
+	},
+	{ /* sentinel */ },
+};
+
+MODULE_DEVICE_TABLE(of, snd_pifi_40_of_match);
+
+static struct platform_driver snd_pifi_40_driver = {
+	.driver = {
+		.name = "snd-pifi-40",
+		.owner = THIS_MODULE,
+		.of_match_table = snd_pifi_40_of_match,
+	},
+	.probe = snd_pifi_40_probe,
+	.remove = snd_pifi_40_remove,
+};
+
+module_platform_driver(snd_pifi_40_driver);
+
+MODULE_AUTHOR("David Knell <david.knell@gmail.com>");
+MODULE_DESCRIPTION("ALSA ASoC Machine Driver for PiFi-40");
+MODULE_LICENSE("GPL v2");
