openwrt/target/linux/brcm2708/patches-4.19/950-0086-ASoC-Create-a-generic-Pi-Hat-WM8804-driver.patch

From 6af5a0adda5b782ad2e134b405ca168895c89b0c Mon Sep 17 00:00:00 2001
From: Tim Gover <tim.gover@raspberrypi.org>
Date: Sat, 21 Jul 2018 20:07:46 +0100
Subject: [PATCH] ASoC: Create a generic Pi Hat WM8804 driver

Reduce the amount of duplicated code by creating a generic driver for
Pi Hat digi cards using the WM8804 codec.

This replaces the
Allo DigiOne, Hifiberry Digi/Pro, JustBoom Digi and IQAudIO Digi
dedicate soundcard drivers with a generic driver.

There are no significant changes to the runtime behavior of the drivers
and end users should not have to change any configuration settings
after upgrading.

Minor changes
* Check the return value of snd_soc_component_update_bits
* Added some pr_debug tracing
* Various checkpatch tidyups
* Updated allodigi-one to use use 128FS at > 96 Khz. This appears to
  be an omission in the original driver code so followed the Hifiberry
  DAC driver approach.
---
 sound/soc/bcm/rpi-wm8804-soundcard.c | 428 +++++++++++++++++++++++++++
 1 file changed, 428 insertions(+)
 create mode 100644 sound/soc/bcm/rpi-wm8804-soundcard.c

--- /dev/null
+++ b/sound/soc/bcm/rpi-wm8804-soundcard.c
@@ -0,0 +1,428 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * rpi--wm8804.c -- ALSA SoC Raspberry Pi soundcard.
+ *
+ * Copyright (C) 2018 Raspberry Pi.
+ *
+ * Authors: Tim Gover <tim.gover@raspberrypi.org>
+ *
+ * Generic driver for Pi Hat WM8804 digi sounds cards
+ *
+ * Based upon code from:
+ * justboom-digi.c
+ * by Milan Neskovic <info@justboom.co>
+ *
+ * iqaudio_digi.c
+ * by Daniel Matuschek <info@crazy-audio.com>
+ *
+ * allo-digione.c
+ * by Baswaraj <jaikumar@cem-solutions.net>
+ *
+ * hifiberry-digi.c
+ * Daniel Matuschek <info@crazy-audio.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/gpio/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/module.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+
+#include "../codecs/wm8804.h"
+
+struct wm8804_clk_cfg {
+	unsigned int sysclk_freq;
+	unsigned int mclk_freq;
+	unsigned int mclk_div;
+};
+
+/* Parameters for generic functions */
+struct snd_rpi_wm8804_drvdata {
+	/* Required - pointer to the DAI structure */
+	struct snd_soc_dai_link *dai;
+	/* Required - snd_soc_card name */
+	const char *card_name;
+	/* Optional- Overrides the module paramter */
+	unsigned short auto_shutdown_output;
+	/* Optional DT node names if card info is defined in DT */
+	const char *card_name_dt;
+	const char *dai_name_dt;
+	const char *dai_stream_name_dt;
+	/* Optional probe extension - called prior to register_card */
+	int (*probe)(struct platform_device *pdev);
+};
+
+static short int auto_shutdown_output;
+module_param(auto_shutdown_output, short, 0660);
+MODULE_PARM_DESC(auto_shutdown_output, "Shutdown SP/DIF output if playback is stopped");
+
+static struct gpio_desc *snd_clk44gpio;
+static struct gpio_desc *snd_clk48gpio;
+
+#define CLK_44EN_RATE 22579200UL
+#define CLK_48EN_RATE 24576000UL
+
+static int snd_rpi_wm8804_init(struct snd_soc_pcm_runtime *rtd)
+{
+	struct snd_soc_component *component = rtd->codec_dai->component;
+	int rc;
+
+	pr_debug("%s\n", __func__);
+
+	rc = snd_soc_component_update_bits(component, WM8804_PWRDN, 0x4, 0x0);
+	return rc < 0 ? rc : 0;
+}
+
+static int snd_rpi_wm8804_digi_startup(struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct snd_soc_component *component = rtd->codec_dai->component;
+	int rc;
+
+	pr_debug("%s\n", __func__);
+
+	rc = snd_soc_component_update_bits(component, WM8804_PWRDN, 0x3c, 0x00);
+	return rc < 0 ? rc : 0;
+}
+
+static void snd_rpi_wm8804_digi_shutdown(struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct snd_soc_component *component = rtd->codec_dai->component;
+
+	pr_debug("%s %d\n", __func__, auto_shutdown_output);
+
+	if (auto_shutdown_output)
+		snd_soc_component_update_bits(component, WM8804_PWRDN,
+				0x3c, 0x3c);
+}
+
+static unsigned int snd_rpi_wm8804_enable_clock(unsigned int samplerate)
+{
+	switch (samplerate) {
+	case 11025:
+	case 22050:
+	case 44100:
+	case 88200:
+	case 176400:
+		gpiod_set_value_cansleep(snd_clk44gpio, 1);
+		gpiod_set_value_cansleep(snd_clk48gpio, 0);
+		return CLK_44EN_RATE;
+	default:
+		gpiod_set_value_cansleep(snd_clk48gpio, 1);
+		gpiod_set_value_cansleep(snd_clk44gpio, 0);
+		return CLK_48EN_RATE;
+	}
+}
+
+static void snd_rpi_wm8804_clk_cfg(unsigned int samplerate,
+		struct wm8804_clk_cfg *clk_cfg)
+{
+	clk_cfg->mclk_freq = 0;
+	clk_cfg->mclk_div = 1;
+	clk_cfg->sysclk_freq = 27000000;
+
+	if (samplerate <= 96000) {
+		clk_cfg->mclk_freq = samplerate * 256;
+		clk_cfg->mclk_div = WM8804_MCLKDIV_256FS;
+	} else {
+		clk_cfg->mclk_freq = samplerate * 128;
+		clk_cfg->mclk_div = WM8804_MCLKDIV_128FS;
+	}
+
+	if (!(IS_ERR(snd_clk44gpio) || IS_ERR(snd_clk48gpio)))
+		clk_cfg->sysclk_freq = snd_rpi_wm8804_enable_clock(samplerate);
+}
+
+static int snd_rpi_wm8804_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 *codec_dai = rtd->codec_dai;
+	struct snd_soc_component *component = rtd->codec_dai->component;
+	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
+	int sampling_freq = 1;
+	int ret;
+	struct wm8804_clk_cfg clk_cfg;
+	int samplerate = params_rate(params);
+
+	snd_rpi_wm8804_clk_cfg(samplerate, &clk_cfg);
+
+	pr_debug("%s samplerate: %d mclk_freq: %u mclk_div: %u sysclk: %u\n",
+			__func__, samplerate, clk_cfg.mclk_freq,
+			clk_cfg.mclk_div, clk_cfg.sysclk_freq);
+
+	switch (samplerate) {
+	case 32000:
+		sampling_freq = 0x03;
+		break;
+	case 44100:
+		sampling_freq = 0x00;
+		break;
+	case 48000:
+		sampling_freq = 0x02;
+		break;
+	case 88200:
+		sampling_freq = 0x08;
+		break;
+	case 96000:
+		sampling_freq = 0x0a;
+		break;
+	case 176400:
+		sampling_freq = 0x0c;
+		break;
+	case 192000:
+		sampling_freq = 0x0e;
+		break;
+	default:
+		dev_err(rtd->card->dev,
+		"Failed to set WM8804 SYSCLK, unsupported samplerate %d\n",
+		samplerate);
+	}
+
+	snd_soc_dai_set_clkdiv(codec_dai, WM8804_MCLK_DIV, clk_cfg.mclk_div);
+	snd_soc_dai_set_pll(codec_dai, 0, 0,
+			clk_cfg.sysclk_freq, clk_cfg.mclk_freq);
+
+	ret = snd_soc_dai_set_sysclk(codec_dai, WM8804_TX_CLKSRC_PLL,
+			clk_cfg.sysclk_freq, SND_SOC_CLOCK_OUT);
+	if (ret < 0) {
+		dev_err(rtd->card->dev,
+		"Failed to set WM8804 SYSCLK: %d\n", ret);
+		return ret;
+	}
+
+	/* Enable TX output */
+	snd_soc_component_update_bits(component, WM8804_PWRDN, 0x4, 0x0);
+
+	/* Power on */
+	snd_soc_component_update_bits(component, WM8804_PWRDN, 0x9, 0);
+
+	/* set sampling frequency status bits */
+	snd_soc_component_update_bits(component, WM8804_SPDTX4, 0x0f,
+			sampling_freq);
+
+	return snd_soc_dai_set_bclk_ratio(cpu_dai, 64);
+}
+
+static struct snd_soc_ops snd_rpi_wm8804_ops = {
+	.hw_params = snd_rpi_wm8804_hw_params,
+	.startup   = snd_rpi_wm8804_digi_startup,
+	.shutdown  = snd_rpi_wm8804_digi_shutdown,
+};
+
+static struct snd_soc_dai_link snd_justboom_digi_dai[] = {
+{
+	.name        = "JustBoom Digi",
+	.stream_name = "JustBoom Digi HiFi",
+},
+};
+
+static struct snd_rpi_wm8804_drvdata drvdata_justboom_digi = {
+	.card_name            = "snd_rpi_justboom_digi",
+	.dai                  = snd_justboom_digi_dai,
+	.auto_shutdown_output = 1,
+};
+
+static struct snd_soc_dai_link snd_iqaudio_digi_dai[] = {
+{
+	.name        = "IQAudIO Digi",
+	.stream_name = "IQAudIO Digi HiFi",
+},
+};
+
+static struct snd_rpi_wm8804_drvdata drvdata_iqaudio_digi = {
+	.card_name          = "IQAudIODigi",
+	.dai                = snd_iqaudio_digi_dai,
+	.card_name_dt       = "wm8804-digi,card-name",
+	.dai_name_dt        = "wm8804-digi,dai-name",
+	.dai_stream_name_dt = "wm8804-digi,dai-stream-name",
+};
+
+static int snd_allo_digione_probe(struct platform_device *pdev)
+{
+	pr_debug("%s\n", __func__);
+
+	if (IS_ERR(snd_clk44gpio) || IS_ERR(snd_clk48gpio)) {
+		dev_err(&pdev->dev, "devm_gpiod_get() failed\n");
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static struct snd_soc_dai_link snd_allo_digione_dai[] = {
+{
+	.name        = "Allo DigiOne",
+	.stream_name = "Allo DigiOne HiFi",
+},
+};
+
+static struct snd_rpi_wm8804_drvdata drvdata_allo_digione = {
+	.card_name = "snd_allo_digione",
+	.dai       = snd_allo_digione_dai,
+	.probe     = snd_allo_digione_probe,
+};
+
+static struct snd_soc_dai_link snd_hifiberry_digi_dai[] = {
+{
+	.name        = "HifiBerry Digi",
+	.stream_name = "HifiBerry Digi HiFi",
+},
+};
+
+static int snd_hifiberry_digi_probe(struct platform_device *pdev)
+{
+	pr_debug("%s\n", __func__);
+
+	if (IS_ERR(snd_clk44gpio) || IS_ERR(snd_clk48gpio))
+		return 0;
+
+	snd_hifiberry_digi_dai->name = "HiFiBerry Digi+ Pro";
+	snd_hifiberry_digi_dai->stream_name = "HiFiBerry Digi+ Pro HiFi";
+	return 0;
+}
+
+static struct snd_rpi_wm8804_drvdata drvdata_hifiberry_digi = {
+	.card_name = "snd_rpi_hifiberry_digi",
+	.dai       = snd_hifiberry_digi_dai,
+	.probe     = snd_hifiberry_digi_probe,
+};
+
+static const struct of_device_id snd_rpi_wm8804_of_match[] = {
+	{ .compatible = "justboom,justboom-digi",
+		.data = (void *) &drvdata_justboom_digi },
+	{ .compatible = "iqaudio,wm8804-digi",
+		.data = (void *) &drvdata_iqaudio_digi },
+	{ .compatible = "allo,allo-digione",
+		.data = (void *) &drvdata_allo_digione },
+	{ .compatible = "hifiberry,hifiberry-digi",
+		.data = (void *) &drvdata_hifiberry_digi },
+	{},
+};
+
+static struct snd_soc_card snd_rpi_wm8804 = {
+	.driver_name  = "RPi-WM8804",
+	.owner        = THIS_MODULE,
+	.dai_link     = NULL,
+	.num_links    = 1,
+};
+
+static int snd_rpi_wm8804_probe(struct platform_device *pdev)
+{
+	int ret = 0;
+	const struct of_device_id *of_id;
+
+	snd_rpi_wm8804.dev = &pdev->dev;
+	of_id = of_match_node(snd_rpi_wm8804_of_match, pdev->dev.of_node);
+
+	if (pdev->dev.of_node && of_id->data) {
+		struct device_node *i2s_node;
+		struct snd_rpi_wm8804_drvdata *drvdata =
+			(struct snd_rpi_wm8804_drvdata *) of_id->data;
+		struct snd_soc_dai_link *dai = drvdata->dai;
+
+		snd_soc_card_set_drvdata(&snd_rpi_wm8804, drvdata);
+
+		if (!dai->init)
+			dai->init = snd_rpi_wm8804_init;
+		if (!dai->ops)
+			dai->ops = &snd_rpi_wm8804_ops;
+		if (!dai->codec_dai_name)
+			dai->codec_dai_name = "wm8804-spdif";
+		if (!dai->codec_name)
+			dai->codec_name = "wm8804.1-003b";
+		if (!dai->dai_fmt)
+			dai->dai_fmt = SND_SOC_DAIFMT_I2S |
+				SND_SOC_DAIFMT_NB_NF |
+				SND_SOC_DAIFMT_CBM_CFM;
+
+		if (drvdata->auto_shutdown_output)
+			auto_shutdown_output = 1;
+
+		snd_rpi_wm8804.dai_link = dai;
+		i2s_node = of_parse_phandle(pdev->dev.of_node,
+				"i2s-controller", 0);
+		if (!i2s_node) {
+			pr_err("Failed to find i2s-controller DT node\n");
+			return -ENODEV;
+		}
+
+		snd_rpi_wm8804.name = drvdata->card_name;
+
+		/* If requested by in drvdata get card & DAI names from DT */
+		if (drvdata->card_name_dt)
+			of_property_read_string(i2s_node,
+					drvdata->card_name_dt,
+					&snd_rpi_wm8804.name);
+
+		if (drvdata->dai_name_dt)
+			of_property_read_string(i2s_node,
+					drvdata->dai_name_dt,
+					&dai->name);
+
+		if (drvdata->dai_stream_name_dt)
+			of_property_read_string(i2s_node,
+					drvdata->dai_stream_name_dt,
+					&dai->stream_name);
+
+		dai->cpu_of_node = i2s_node;
+		dai->platform_of_node = i2s_node;
+
+		/*
+		 * clk44gpio and clk48gpio are not required by all cards so
+		 * don't check the error status.
+		 */
+		snd_clk44gpio =
+			devm_gpiod_get(&pdev->dev, "clock44", GPIOD_OUT_LOW);
+
+		snd_clk48gpio =
+			devm_gpiod_get(&pdev->dev, "clock48", GPIOD_OUT_LOW);
+
+		if (drvdata->probe) {
+			ret = drvdata->probe(pdev);
+			if (ret < 0) {
+				dev_err(&pdev->dev, "Custom probe failed %d\n",
+						ret);
+				return ret;
+			}
+		}
+
+		pr_debug("%s card: %s dai: %s stream: %s\n", __func__,
+				snd_rpi_wm8804.name,
+				dai->name, dai->stream_name);
+	}
+
+	ret = devm_snd_soc_register_card(&pdev->dev, &snd_rpi_wm8804);
+	if (ret && ret != -EPROBE_DEFER)
+		dev_err(&pdev->dev, "Failed to register card %d\n", ret);
+
+	return ret;
+}
+
+static struct platform_driver snd_rpi_wm8804_driver = {
+	.driver = {
+		.name           = "snd-rpi-wm8804",
+		.owner          = THIS_MODULE,
+		.of_match_table = snd_rpi_wm8804_of_match,
+	},
+	.probe  = snd_rpi_wm8804_probe,
+};
+MODULE_DEVICE_TABLE(of, snd_rpi_wm8804_of_match);
+
+module_platform_driver(snd_rpi_wm8804_driver);
+
+MODULE_AUTHOR("Tim Gover <tim.gover@raspberrypi.org>");
+MODULE_DESCRIPTION("ASoC Raspberry Pi Hat generic digi driver for WM8804 based cards");
+MODULE_LICENSE("GPL v2");