From 846864bceccdafbed86c1b1766500861547b0da9 Mon Sep 17 00:00:00 2001
From: Matt Flax <flatmax@flatmax.org>
Date: Wed, 8 Mar 2017 20:04:13 +1100
Subject: [PATCH] Add support for the AudioInjector.net Octo sound card

AudioInjector Octo: sample rates, regulators, reset

This patch adds new sample rates to the Audioinjector Octo sound card. The
new supported rates are (in kHz) :
96, 48, 32, 24, 16, 8, 88.2, 44.1, 29.4, 22.05, 14.7

Reference the bcm270x DT regulators in the overlay.

This patch adds a reset GPIO for the AudioInjector.net octo sound card.

Audioinjector octo : Make the playback and capture symmetric

This patch ensures that the sample rate and channel count of the audioinjector
octo sound card are symmetric.

audioinjector-octo: Add continuous clock feature

By user request, add a switch to prevent the clocks being stopped when
the stream is paused, stopped or shutdown. Provide access to the switch
by adding a 'non-stop-clocks' parameter to the audioinjector-addons
overlay.

See: https://github.com/raspberrypi/linux/issues/2409

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
---
 sound/soc/bcm/audioinjector-octo-soundcard.c | 336 +++++++++++++++++++
 1 file changed, 336 insertions(+)
 create mode 100644 sound/soc/bcm/audioinjector-octo-soundcard.c

--- /dev/null
+++ b/sound/soc/bcm/audioinjector-octo-soundcard.c
@@ -0,0 +1,336 @@
+/*
+ * ASoC Driver for AudioInjector Pi octo channel soundcard (hat)
+ *
+ *  Created on: 27-October-2016
+ *      Author: flatmax@flatmax.org
+ *              based on audioinjector-pi-soundcard.c
+ *
+ * Copyright (C) 2016 Flatmax Pty. Ltd.
+ *
+ * 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/types.h>
+#include <linux/gpio/consumer.h>
+
+#include <sound/core.h>
+#include <sound/soc.h>
+#include <sound/pcm_params.h>
+#include <sound/control.h>
+
+static struct gpio_descs *mult_gpios;
+static struct gpio_desc *codec_rst_gpio;
+static unsigned int audioinjector_octo_rate;
+static bool non_stop_clocks;
+
+static const unsigned int audioinjector_octo_rates[] = {
+	96000, 48000, 32000, 24000, 16000, 8000, 88200, 44100, 29400, 22050, 14700,
+};
+
+static struct snd_pcm_hw_constraint_list audioinjector_octo_constraints = {
+	.list = audioinjector_octo_rates,
+	.count = ARRAY_SIZE(audioinjector_octo_rates),
+};
+
+static int audioinjector_octo_dai_init(struct snd_soc_pcm_runtime *rtd)
+{
+	return snd_soc_dai_set_bclk_ratio(rtd->cpu_dai, 64);
+}
+
+static int audioinjector_octo_startup(struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	rtd->cpu_dai->driver->playback.channels_min = 8;
+	rtd->cpu_dai->driver->playback.channels_max = 8;
+	rtd->cpu_dai->driver->capture.channels_min = 8;
+	rtd->cpu_dai->driver->capture.channels_max = 8;
+	rtd->codec_dai->driver->capture.channels_max = 8;
+	
+	snd_pcm_hw_constraint_list(substream->runtime, 0,
+				SNDRV_PCM_HW_PARAM_RATE,
+				&audioinjector_octo_constraints);
+
+	return 0;
+}
+
+static void audioinjector_octo_shutdown(struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	rtd->cpu_dai->driver->playback.channels_min = 2;
+	rtd->cpu_dai->driver->playback.channels_max = 2;
+	rtd->cpu_dai->driver->capture.channels_min = 2;
+	rtd->cpu_dai->driver->capture.channels_max = 2;
+	rtd->codec_dai->driver->capture.channels_max = 6;
+}
+
+static int audioinjector_octo_hw_params(struct snd_pcm_substream *substream,
+	struct snd_pcm_hw_params *params)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+
+	// set codec DAI configuration
+	int ret = snd_soc_dai_set_fmt(rtd->codec_dai,
+			SND_SOC_DAIFMT_CBS_CFS|SND_SOC_DAIFMT_DSP_A|
+			SND_SOC_DAIFMT_NB_NF);
+	if (ret < 0)
+		return ret;
+
+	// set cpu DAI configuration
+	ret = snd_soc_dai_set_fmt(rtd->cpu_dai,
+			SND_SOC_DAIFMT_CBM_CFM|SND_SOC_DAIFMT_I2S|
+			SND_SOC_DAIFMT_NB_NF);
+	if (ret < 0)
+		return ret;
+
+	audioinjector_octo_rate = params_rate(params);
+
+	// Set the correct sysclock for the codec
+	switch (audioinjector_octo_rate) {
+	case 96000:
+	case 48000:
+		return snd_soc_dai_set_sysclk(rtd->codec_dai, 0, 49152000,
+									0);
+		break;
+	case 24000:
+		return snd_soc_dai_set_sysclk(rtd->codec_dai, 0, 49152000/2,
+									0);
+		break;
+	case 32000:
+	case 16000:
+		return snd_soc_dai_set_sysclk(rtd->codec_dai, 0, 49152000/3,
+									0);
+		break;
+	case 8000:
+		return snd_soc_dai_set_sysclk(rtd->codec_dai, 0, 49152000/6,
+									0);
+		break;
+	case 88200:
+	case 44100:
+		return snd_soc_dai_set_sysclk(rtd->codec_dai, 0, 45185400,
+									0);
+		break;
+	case 22050:
+		return snd_soc_dai_set_sysclk(rtd->codec_dai, 0, 45185400/2,
+									0);
+		break;
+	case 29400:
+	case 14700:
+		return snd_soc_dai_set_sysclk(rtd->codec_dai, 0, 45185400/3,
+									0);
+		break;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int audioinjector_octo_trigger(struct snd_pcm_substream *substream,
+								int cmd){
+	int mult[4];
+
+	memset(mult, 0, sizeof(mult));
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		if (!non_stop_clocks)
+			break;
+		/* Drop through... */
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		switch (audioinjector_octo_rate) {
+		case 96000:
+			mult[3] = 1;
+		case 88200:
+			mult[1] = 1;
+			mult[2] = 1;
+			break;
+		case 48000:
+			mult[3] = 1;
+		case 44100:
+			mult[2] = 1;
+			break;
+		case 32000:
+			mult[3] = 1;
+		case 29400:
+			mult[0] = 1;
+			mult[1] = 1;
+			break;
+		case 24000:
+			mult[3] = 1;
+		case 22050:
+			mult[1] = 1;
+			break;
+		case 16000:
+			mult[3] = 1;
+		case 14700:
+			mult[0] = 1;
+			break;
+		case 8000:
+			mult[3] = 1;
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+	default:
+		return -EINVAL;
+	}
+	gpiod_set_array_value_cansleep(mult_gpios->ndescs, mult_gpios->desc,
+									mult);
+
+	return 0;
+}
+
+static struct snd_soc_ops audioinjector_octo_ops = {
+	.startup	= audioinjector_octo_startup,
+	.shutdown	= audioinjector_octo_shutdown,
+	.hw_params = audioinjector_octo_hw_params,
+	.trigger = audioinjector_octo_trigger,
+};
+
+static struct snd_soc_dai_link audioinjector_octo_dai[] = {
+	{
+		.name = "AudioInjector Octo",
+		.stream_name = "AudioInject-HIFI",
+		.codec_dai_name = "cs42448",
+		.ops = &audioinjector_octo_ops,
+		.init = audioinjector_octo_dai_init,
+		.symmetric_rates = 1,
+		.symmetric_channels = 1,
+	},
+};
+
+static const struct snd_soc_dapm_widget audioinjector_octo_widgets[] = {
+	SND_SOC_DAPM_OUTPUT("OUTPUTS0"),
+	SND_SOC_DAPM_OUTPUT("OUTPUTS1"),
+	SND_SOC_DAPM_OUTPUT("OUTPUTS2"),
+	SND_SOC_DAPM_OUTPUT("OUTPUTS3"),
+	SND_SOC_DAPM_INPUT("INPUTS0"),
+	SND_SOC_DAPM_INPUT("INPUTS1"),
+	SND_SOC_DAPM_INPUT("INPUTS2"),
+};
+
+static const struct snd_soc_dapm_route audioinjector_octo_route[] = {
+	/* Balanced outputs */
+	{"OUTPUTS0", NULL, "AOUT1L"},
+	{"OUTPUTS0", NULL, "AOUT1R"},
+	{"OUTPUTS1", NULL, "AOUT2L"},
+	{"OUTPUTS1", NULL, "AOUT2R"},
+	{"OUTPUTS2", NULL, "AOUT3L"},
+	{"OUTPUTS2", NULL, "AOUT3R"},
+	{"OUTPUTS3", NULL, "AOUT4L"},
+	{"OUTPUTS3", NULL, "AOUT4R"},
+
+	/* Balanced inputs */
+	{"AIN1L", NULL, "INPUTS0"},
+	{"AIN1R", NULL, "INPUTS0"},
+	{"AIN2L", NULL, "INPUTS1"},
+	{"AIN2R", NULL, "INPUTS1"},
+	{"AIN3L", NULL, "INPUTS2"},
+	{"AIN3R", NULL, "INPUTS2"},
+};
+
+static struct snd_soc_card snd_soc_audioinjector_octo = {
+	.name = "audioinjector-octo-soundcard",
+	.dai_link = audioinjector_octo_dai,
+	.num_links = ARRAY_SIZE(audioinjector_octo_dai),
+
+	.dapm_widgets = audioinjector_octo_widgets,
+	.num_dapm_widgets = ARRAY_SIZE(audioinjector_octo_widgets),
+	.dapm_routes = audioinjector_octo_route,
+	.num_dapm_routes = ARRAY_SIZE(audioinjector_octo_route),
+};
+
+static int audioinjector_octo_probe(struct platform_device *pdev)
+{
+	struct snd_soc_card *card = &snd_soc_audioinjector_octo;
+	int ret;
+
+	card->dev = &pdev->dev;
+
+	if (pdev->dev.of_node) {
+		struct snd_soc_dai_link *dai = &audioinjector_octo_dai[0];
+		struct device_node *i2s_node =
+					of_parse_phandle(pdev->dev.of_node,
+							"i2s-controller", 0);
+		struct device_node *codec_node =
+					of_parse_phandle(pdev->dev.of_node,
+								"codec", 0);
+
+		mult_gpios = devm_gpiod_get_array_optional(&pdev->dev, "mult",
+								GPIOD_OUT_LOW);
+		if (IS_ERR(mult_gpios))
+			return PTR_ERR(mult_gpios);
+
+		codec_rst_gpio = devm_gpiod_get_optional(&pdev->dev, "reset",
+								GPIOD_OUT_LOW);
+		if (IS_ERR(codec_rst_gpio))
+			return PTR_ERR(codec_rst_gpio);
+
+		non_stop_clocks = of_property_read_bool(pdev->dev.of_node, "non-stop-clocks");
+
+		if (codec_rst_gpio)
+			gpiod_set_value(codec_rst_gpio, 1);
+		msleep(500);
+		if (codec_rst_gpio)
+			gpiod_set_value(codec_rst_gpio, 0);
+		msleep(500);
+		if (codec_rst_gpio)
+			gpiod_set_value(codec_rst_gpio, 1);
+		msleep(500);
+
+		if (i2s_node && codec_node) {
+			dai->cpu_dai_name = NULL;
+			dai->cpu_of_node = i2s_node;
+			dai->platform_name = NULL;
+			dai->platform_of_node = i2s_node;
+			dai->codec_name = NULL;
+			dai->codec_of_node = codec_node;
+		} else
+			if (!dai->cpu_of_node) {
+				dev_err(&pdev->dev,
+				"i2s-controller missing or invalid in DT\n");
+				return -EINVAL;
+			} else {
+				dev_err(&pdev->dev,
+				"Property 'codec' missing or invalid\n");
+				return -EINVAL;
+			}
+	}
+
+	ret = devm_snd_soc_register_card(&pdev->dev, card);
+	if (ret != 0)
+		dev_err(&pdev->dev, "snd_soc_register_card failed (%d)\n", ret);
+	return ret;
+}
+
+static const struct of_device_id audioinjector_octo_of_match[] = {
+	{ .compatible = "ai,audioinjector-octo-soundcard", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, audioinjector_octo_of_match);
+
+static struct platform_driver audioinjector_octo_driver = {
+	.driver	= {
+		.name			= "audioinjector-octo",
+		.owner			= THIS_MODULE,
+		.of_match_table = audioinjector_octo_of_match,
+	},
+	.probe	= audioinjector_octo_probe,
+};
+
+module_platform_driver(audioinjector_octo_driver);
+MODULE_AUTHOR("Matt Flax <flatmax@flatmax.org>");
+MODULE_DESCRIPTION("AudioInjector.net octo Soundcard");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:audioinjector-octo-soundcard");