Openwrt/target/linux/bcm27xx/patches-5.4/950-0080-ASoC-Create-a-generic-Pi-Hat-WM8804-driver.patch

From e211a67304ac3104fb9ee1a2524f3ffbed5c2284 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.

ASoC: rpi-wm8804-soundcard: use modern dai_link style

Signed-off-by: Matthias Reichl <hias@horus.com>

rpi-wm8804-soundcard: drop PWRDN register writes

Since kernel 4.0 the PWRDN register bits are under DAPM
control from the wm8804 driver.

Drop code that modifies that register to avoid interfering
with DAPM.

Signed-off-by: Matthias Reichl <hias@horus.com>

rpi-wm8804-soundcard: configure wm8804 clocks only on rate change

This should avoid clicks when stopping and immediately afterwards
starting a stream with the same samplerate as before.

Signed-off-by: Matthias Reichl <hias@horus.com>

rpi-wm8804-soundcard: Fixed MCLKDIV for Allo Digione

The Allo Digione board wants a fixed MCLKDIV of 256.

See: https://github.com/raspberrypi/linux/issues/3296

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
---
 sound/soc/bcm/rpi-wm8804-soundcard.c | 410 +++++++++++++++++++++++++++
 1 file changed, 410 insertions(+)
 create mode 100644 sound/soc/bcm/rpi-wm8804-soundcard.c

--- /dev/null
+++ b/sound/soc/bcm/rpi-wm8804-soundcard.c
@@ -0,0 +1,410 @@
+// 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 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 struct gpio_desc *snd_clk44gpio;
+static struct gpio_desc *snd_clk48gpio;
+static int wm8804_samplerate = 0;
+
+/* Forward declarations */
+static struct snd_soc_dai_link snd_allo_digione_dai[];
+static struct snd_soc_card snd_rpi_wm8804;
+
+
+#define CLK_44EN_RATE 22579200UL
+#define CLK_48EN_RATE 24576000UL
+
+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->sysclk_freq = 27000000;
+
+	if (samplerate <= 96000 ||
+	    snd_rpi_wm8804.dai_link == snd_allo_digione_dai) {
+		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);
+
+	if (samplerate == wm8804_samplerate)
+		return 0;
+
+	/* clear until all clocks are setup properly */
+	wm8804_samplerate = 0;
+
+	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;
+	}
+
+	wm8804_samplerate = samplerate;
+
+	/* 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,
+};
+
+SND_SOC_DAILINK_DEFS(justboom_digi,
+	DAILINK_COMP_ARRAY(COMP_EMPTY()),
+	DAILINK_COMP_ARRAY(COMP_EMPTY()),
+	DAILINK_COMP_ARRAY(COMP_EMPTY()));
+
+static struct snd_soc_dai_link snd_justboom_digi_dai[] = {
+{
+	.name        = "JustBoom Digi",
+	.stream_name = "JustBoom Digi HiFi",
+	SND_SOC_DAILINK_REG(justboom_digi),
+},
+};
+
+static struct snd_rpi_wm8804_drvdata drvdata_justboom_digi = {
+	.card_name            = "snd_rpi_justboom_digi",
+	.dai                  = snd_justboom_digi_dai,
+};
+
+SND_SOC_DAILINK_DEFS(iqaudio_digi,
+	DAILINK_COMP_ARRAY(COMP_EMPTY()),
+	DAILINK_COMP_ARRAY(COMP_EMPTY()),
+	DAILINK_COMP_ARRAY(COMP_EMPTY()));
+
+static struct snd_soc_dai_link snd_iqaudio_digi_dai[] = {
+{
+	.name        = "IQAudIO Digi",
+	.stream_name = "IQAudIO Digi HiFi",
+	SND_SOC_DAILINK_REG(iqaudio_digi),
+},
+};
+
+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;
+}
+
+SND_SOC_DAILINK_DEFS(allo_digione,
+	DAILINK_COMP_ARRAY(COMP_EMPTY()),
+	DAILINK_COMP_ARRAY(COMP_EMPTY()),
+	DAILINK_COMP_ARRAY(COMP_EMPTY()));
+
+static struct snd_soc_dai_link snd_allo_digione_dai[] = {
+{
+	.name        = "Allo DigiOne",
+	.stream_name = "Allo DigiOne HiFi",
+	SND_SOC_DAILINK_REG(allo_digione),
+},
+};
+
+static struct snd_rpi_wm8804_drvdata drvdata_allo_digione = {
+	.card_name = "snd_allo_digione",
+	.dai       = snd_allo_digione_dai,
+	.probe     = snd_allo_digione_probe,
+};
+
+SND_SOC_DAILINK_DEFS(hifiberry_digi,
+	DAILINK_COMP_ARRAY(COMP_EMPTY()),
+	DAILINK_COMP_ARRAY(COMP_EMPTY()),
+	DAILINK_COMP_ARRAY(COMP_EMPTY()));
+
+static struct snd_soc_dai_link snd_hifiberry_digi_dai[] = {
+{
+	.name        = "HifiBerry Digi",
+	.stream_name = "HifiBerry Digi HiFi",
+	SND_SOC_DAILINK_REG(hifiberry_digi),
+},
+};
+
+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->ops)
+			dai->ops = &snd_rpi_wm8804_ops;
+		if (!dai->codecs->dai_name)
+			dai->codecs->dai_name = "wm8804-spdif";
+		if (!dai->codecs->name)
+			dai->codecs->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;
+
+		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->cpus->of_node = i2s_node;
+		dai->platforms->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");