From 5f1aa4352ca253ca76ee49c51292994d517d7e4e Mon Sep 17 00:00:00 2001
From: Peter Malkin <petermalkin@google.com>
Date: Mon, 27 Mar 2017 16:38:21 -0700
Subject: [PATCH 087/454] Driver support for Google voiceHAT soundcard.

---
 sound/soc/bcm/Kconfig                    |   7 +
 sound/soc/bcm/Makefile                   |   6 +
 sound/soc/bcm/googlevoicehat-codec.c     | 199 +++++++++++++++++++++++
 sound/soc/bcm/googlevoicehat-soundcard.c | 124 ++++++++++++++
 4 files changed, 336 insertions(+)
 create mode 100644 sound/soc/bcm/googlevoicehat-codec.c
 create mode 100644 sound/soc/bcm/googlevoicehat-soundcard.c

--- a/sound/soc/bcm/Kconfig
+++ b/sound/soc/bcm/Kconfig
@@ -18,6 +18,13 @@ config SND_SOC_CYGNUS
 
 	  If you don't know what to do here, say N.
 
+config SND_BCM2708_SOC_GOOGLEVOICEHAT_SOUNDCARD
+	tristate "Support for Google voiceHAT soundcard"
+	depends on SND_BCM2708_SOC_I2S || SND_BCM2835_SOC_I2S
+	select SND_SOC_VOICEHAT
+	help
+          Say Y or M if you want to add support for voiceHAT soundcard.
+
 config SND_BCM2708_SOC_HIFIBERRY_DAC
         tristate "Support for HifiBerry DAC"
         depends on SND_BCM2708_SOC_I2S || SND_BCM2835_SOC_I2S
--- a/sound/soc/bcm/Makefile
+++ b/sound/soc/bcm/Makefile
@@ -8,8 +8,12 @@ snd-soc-cygnus-objs := cygnus-pcm.o cygn
 
 obj-$(CONFIG_SND_SOC_CYGNUS) += snd-soc-cygnus.o
 
+# Google voiceHAT custom codec support
+snd-soc-googlevoicehat-codec-objs := googlevoicehat-codec.o
+
 # BCM2708 Machine Support
 snd-soc-adau1977-adc-objs := adau1977-adc.o
+snd-soc-googlevoicehat-soundcard-objs := googlevoicehat-soundcard.o
 snd-soc-hifiberry-amp-objs := hifiberry_amp.o
 snd-soc-hifiberry-dac-objs := hifiberry_dac.o
 snd-soc-hifiberry-dacplus-objs := hifiberry_dacplus.o
@@ -34,6 +38,8 @@ snd-soc-pisound-objs := pisound.o
 snd-soc-fe-pi-audio-objs := fe-pi-audio.o
 
 obj-$(CONFIG_SND_BCM2708_SOC_ADAU1977_ADC) += snd-soc-adau1977-adc.o
+obj-$(CONFIG_SND_BCM2708_SOC_GOOGLEVOICEHAT_SOUNDCARD) += snd-soc-googlevoicehat-soundcard.o
+obj-$(CONFIG_SND_BCM2708_SOC_GOOGLEVOICEHAT_SOUNDCARD)  += snd-soc-googlevoicehat-codec.o
 obj-$(CONFIG_SND_BCM2708_SOC_HIFIBERRY_AMP) += snd-soc-hifiberry-amp.o
 obj-$(CONFIG_SND_BCM2708_SOC_HIFIBERRY_DAC) += snd-soc-hifiberry-dac.o
 obj-$(CONFIG_SND_BCM2708_SOC_HIFIBERRY_DACPLUS) += snd-soc-hifiberry-dacplus.o
--- /dev/null
+++ b/sound/soc/bcm/googlevoicehat-codec.c
@@ -0,0 +1,199 @@
+/*
+ * Driver for the Google voiceHAT audio codec for Raspberry Pi.
+ *
+ * Author:	Peter Malkin <petermalkin@google.com>
+ *		Copyright 2016
+ *
+ * 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/device.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/version.h>
+#include <sound/pcm.h>
+#include <sound/soc.h>
+#include <sound/soc-dai.h>
+#include <sound/soc-dapm.h>
+
+#define ICS43432_RATE_MIN_HZ 7190  /* from data sheet */
+#define ICS43432_RATE_MAX_HZ 52800 /* from data sheet */
+#define SDMODE_DELAY_MS \
+  5 /* Delay in enabling SDMODE after clock settles to remove pop */
+
+struct voicehat_priv {
+  struct delayed_work enable_sdmode_work;
+  struct gpio_desc *sdmode_gpio;
+  unsigned int sdmode_delay;
+};
+
+static void voicehat_enable_sdmode_work(struct work_struct *work) {
+  struct voicehat_priv *voicehat =
+      container_of(work, struct voicehat_priv, enable_sdmode_work.work);
+  gpiod_set_value(voicehat->sdmode_gpio, 1);
+}
+
+static int voicehat_codec_probe(struct snd_soc_codec *codec) {
+  struct voicehat_priv *voicehat = snd_soc_codec_get_drvdata(codec);
+
+  voicehat->sdmode_gpio = devm_gpiod_get(codec->dev, "sdmode", GPIOD_OUT_LOW);
+  if (IS_ERR(voicehat->sdmode_gpio)) {
+    dev_err(codec->dev, "Unable to allocate GPIO pin\n");
+    return PTR_ERR(voicehat->sdmode_gpio);
+  }
+
+  INIT_DELAYED_WORK(&voicehat->enable_sdmode_work, voicehat_enable_sdmode_work);
+  return 0;
+}
+
+static int voicehat_codec_remove(struct snd_soc_codec *codec) {
+  struct voicehat_priv *voicehat = snd_soc_codec_get_drvdata(codec);
+
+  cancel_delayed_work_sync(&voicehat->enable_sdmode_work);
+
+  return 0;
+}
+
+static const struct snd_soc_dapm_widget voicehat_dapm_widgets[] = {
+    SND_SOC_DAPM_OUTPUT("Speaker"),
+};
+
+static const struct snd_soc_dapm_route voicehat_dapm_routes[] = {
+    {"Speaker", NULL, "HiFi Playback"},
+};
+
+static struct snd_soc_codec_driver voicehat_codec_driver = {
+    .probe = voicehat_codec_probe,
+    .remove = voicehat_codec_remove,
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 9, 0)
+    .component_driver = {
+#endif
+    .dapm_widgets = voicehat_dapm_widgets,
+    .num_dapm_widgets = ARRAY_SIZE(voicehat_dapm_widgets),
+    .dapm_routes = voicehat_dapm_routes,
+    .num_dapm_routes = ARRAY_SIZE(voicehat_dapm_routes),
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 9, 0)
+    },
+#endif
+};
+
+static int voicehat_daiops_trigger(struct snd_pcm_substream *substream, int cmd,
+                                struct snd_soc_dai *dai) {
+  struct snd_soc_codec *codec = dai->codec;
+  struct voicehat_priv *voicehat = snd_soc_codec_get_drvdata(codec);
+
+  if (voicehat->sdmode_delay == 0) return 0;
+
+  dev_dbg(dai->dev, "CMD             %d", cmd);
+  dev_dbg(dai->dev, "Playback Active %d", dai->playback_active);
+  dev_dbg(dai->dev, "Capture Active  %d", dai->capture_active);
+
+  switch (cmd) {
+    case SNDRV_PCM_TRIGGER_START:
+    case SNDRV_PCM_TRIGGER_RESUME:
+    case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+      if (dai->playback_active) {
+        dev_info(dai->dev, "Enabling audio amp...\n");
+        queue_delayed_work(system_power_efficient_wq,
+                           &voicehat->enable_sdmode_work,
+                           msecs_to_jiffies(voicehat->sdmode_delay));
+      }
+      break;
+    case SNDRV_PCM_TRIGGER_STOP:
+    case SNDRV_PCM_TRIGGER_SUSPEND:
+    case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+      if (dai->playback_active) {
+        cancel_delayed_work(&voicehat->enable_sdmode_work);
+        dev_info(dai->dev, "Disabling audio amp...\n");
+        gpiod_set_value(voicehat->sdmode_gpio, 0);
+      }
+      break;
+  }
+  return 0;
+}
+
+static const struct snd_soc_dai_ops voicehat_dai_ops = {
+    .trigger = voicehat_daiops_trigger,
+};
+
+static struct snd_soc_dai_driver voicehat_dai = {
+    .name = "voicehat-hifi",
+    .capture = {.stream_name = "HiFi Capture",
+                .channels_min = 2,
+                .channels_max = 2,
+                .rates = SNDRV_PCM_RATE_48000,
+                .formats = SNDRV_PCM_FMTBIT_S32_LE},
+    .playback = {.stream_name = "HiFi Playback",
+                 .channels_min = 2,
+                 .channels_max = 2,
+                 .rates = SNDRV_PCM_RATE_48000,
+                 .formats = SNDRV_PCM_FMTBIT_S32_LE},
+    .ops = &voicehat_dai_ops,
+    .symmetric_rates = 1};
+
+#ifdef CONFIG_OF
+static const struct of_device_id voicehat_ids[] = {
+    {
+        .compatible = "google,voicehat",
+    },
+    {}};
+MODULE_DEVICE_TABLE(of, voicehat_ids);
+#endif
+
+static int voicehat_platform_probe(struct platform_device *pdev) {
+  struct voicehat_priv *voicehat;
+  int ret;
+
+  voicehat = devm_kzalloc(&pdev->dev, sizeof(*voicehat), GFP_KERNEL);
+  if (!voicehat) return -ENOMEM;
+
+  ret = device_property_read_u32(&pdev->dev, "voicehat_sdmode_delay",
+                                 &voicehat->sdmode_delay);
+
+  if (ret) {
+    voicehat->sdmode_delay = SDMODE_DELAY_MS;
+    dev_info(&pdev->dev,
+             "property 'voicehat_sdmode_delay' not found default 5 mS");
+  } else {
+    dev_info(&pdev->dev, "property 'voicehat_sdmode_delay' found delay= %d mS",
+             voicehat->sdmode_delay);
+  }
+
+  dev_set_drvdata(&pdev->dev, voicehat);
+
+  return snd_soc_register_codec(&pdev->dev, &voicehat_codec_driver, &voicehat_dai, 1);
+}
+
+static int voicehat_platform_remove(struct platform_device *pdev) {
+  snd_soc_unregister_codec(&pdev->dev);
+  return 0;
+}
+
+static struct platform_driver voicehat_driver = {
+    .driver =
+        {
+            .name = "voicehat-codec", .of_match_table = of_match_ptr(voicehat_ids),
+        },
+    .probe = voicehat_platform_probe,
+    .remove = voicehat_platform_remove,
+};
+
+module_platform_driver(voicehat_driver);
+
+MODULE_DESCRIPTION("Google voiceHAT Codec driver");
+MODULE_AUTHOR("Peter Malkin <petermalkin@google.com>");
+MODULE_LICENSE("GPL v2");
--- /dev/null
+++ b/sound/soc/bcm/googlevoicehat-soundcard.c
@@ -0,0 +1,124 @@
+/*
+ * ASoC Driver for Google voiceHAT SoundCard
+ *
+ * Author: Peter Malkin <petermalkin@google.com>
+ *         Copyright 2016
+ *
+ * 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 <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <sound/jack.h>
+
+static int snd_rpi_googlevoicehat_soundcard_init(struct snd_soc_pcm_runtime *rtd)
+{
+	return 0;
+}
+
+static int snd_rpi_googlevoicehat_soundcard_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_rpi_googlevoicehat_soundcard_ops = {
+	.hw_params = snd_rpi_googlevoicehat_soundcard_hw_params,
+};
+
+static struct snd_soc_dai_link snd_rpi_googlevoicehat_soundcard_dai[] = {
+{
+	.name		= "Google voiceHAT SoundCard",
+	.stream_name	= "Google voiceHAT SoundCard HiFi",
+	.cpu_dai_name	= "bcm2708-i2s.0",
+	.codec_dai_name	= "voicehat-hifi",
+	.platform_name	= "bcm2708-i2s.0",
+	.codec_name	= "voicehat-codec",
+	.dai_fmt	= SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_NB_NF |
+				SND_SOC_DAIFMT_CBS_CFS,
+	.ops		= &snd_rpi_googlevoicehat_soundcard_ops,
+	.init		= snd_rpi_googlevoicehat_soundcard_init,
+},
+};
+
+/* audio machine driver */
+static struct snd_soc_card snd_rpi_googlevoicehat_soundcard = {
+	.name         = "snd_rpi_googlevoicehat_soundcard",
+	.owner        = THIS_MODULE,
+	.dai_link     = snd_rpi_googlevoicehat_soundcard_dai,
+	.num_links    = ARRAY_SIZE(snd_rpi_googlevoicehat_soundcard_dai),
+};
+
+static int snd_rpi_googlevoicehat_soundcard_probe(struct platform_device *pdev)
+{
+	int ret = 0;
+
+	snd_rpi_googlevoicehat_soundcard.dev = &pdev->dev;
+
+	if (pdev->dev.of_node) {
+		struct device_node *i2s_node;
+		struct snd_soc_dai_link *dai = &snd_rpi_googlevoicehat_soundcard_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;
+		}
+	}
+
+	ret = snd_soc_register_card(&snd_rpi_googlevoicehat_soundcard);
+	if (ret)
+		dev_err(&pdev->dev, "snd_soc_register_card() failed: %d\n", ret);
+
+	return ret;
+}
+
+static int snd_rpi_googlevoicehat_soundcard_remove(struct platform_device *pdev)
+{
+	return snd_soc_unregister_card(&snd_rpi_googlevoicehat_soundcard);
+}
+
+static const struct of_device_id snd_rpi_googlevoicehat_soundcard_of_match[] = {
+	{ .compatible = "googlevoicehat,googlevoicehat-soundcard", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, snd_rpi_googlevoicehat_soundcard_of_match);
+
+static struct platform_driver snd_rpi_googlevoicehat_soundcard_driver = {
+	.driver = {
+		.name   = "snd-googlevoicehat-soundcard",
+		.owner  = THIS_MODULE,
+		.of_match_table = snd_rpi_googlevoicehat_soundcard_of_match,
+	},
+	.probe          = snd_rpi_googlevoicehat_soundcard_probe,
+	.remove         = snd_rpi_googlevoicehat_soundcard_remove,
+};
+
+module_platform_driver(snd_rpi_googlevoicehat_soundcard_driver);
+
+MODULE_AUTHOR("Peter Malkin <petermalkin@google.com>");
+MODULE_DESCRIPTION("ASoC Driver for Google voiceHAT SoundCard");
+MODULE_LICENSE("GPL v2");
