Full hardware codec · register fields, DAC/ADC graph, MCLK coefficients, DAI format, bias state and initialization. Every physical line selectable.
// SPDX-License-Identifier: GPL-2.0-only
/*
* wm8731.c -- WM8731 ALSA SoC Audio driver
*
* Copyright 2005 Openedhand Ltd.
* Copyright 2006-12 Wolfson Microelectronics, plc
* Author: Richard Purdie <richard@openedhand.com>
* Based on wm8753.c by Liam Girdwood
*/
#include <linux/cleanup.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/pm.h>
#include <linux/slab.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <linux/clk.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>
#include <sound/initval.h>
#include <sound/tlv.h>
#include "wm8731.h"
static const char *wm8731_supply_names[WM8731_NUM_SUPPLIES] = {
"AVDD",
"HPVDD",
"DCVDD",
"DBVDD",
};
* wm8731 register cache
static const struct reg_default wm8731_reg_defaults[] = {
{ 0, 0x0097 },
{ 1, 0x0097 },
{ 2, 0x0079 },
{ 3, 0x0079 },
{ 4, 0x000a },
{ 5, 0x0008 },
{ 6, 0x009f },
{ 7, 0x000a },
{ 8, 0x0000 },
{ 9, 0x0000 },
static bool wm8731_volatile(struct device *dev, unsigned int reg)
{
return reg == WM8731_RESET;
}
#define wm8731_reset(m) regmap_write(m, WM8731_RESET, 0)
static const char *wm8731_input_select[] = {"Line In", "Mic"};
static SOC_ENUM_SINGLE_DECL(wm8731_insel_enum,
WM8731_APANA, 2, wm8731_input_select);
static int wm8731_deemph[] = { 0, 32000, 44100, 48000 };
static int wm8731_set_deemph(struct snd_soc_component *component)
struct wm8731_priv *wm8731 = snd_soc_component_get_drvdata(component);
int val, i, best;
/* If we're using deemphasis select the nearest available sample
* rate.
if (wm8731->deemph) {
best = 1;
for (i = 2; i < ARRAY_SIZE(wm8731_deemph); i++) {
if (abs(wm8731_deemph[i] - wm8731->playback_fs) <
abs(wm8731_deemph[best] - wm8731->playback_fs))
best = i;
val = best << 1;
} else {
best = 0;
val = 0;
dev_dbg(component->dev, "Set deemphasis %d (%dHz)\n",
best, wm8731_deemph[best]);
return snd_soc_component_update_bits(component, WM8731_APDIGI, 0x6, val);
static int wm8731_get_deemph(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_value *ucontrol)
struct snd_soc_component *component = snd_kcontrol_chip(kcontrol);
ucontrol->value.integer.value[0] = wm8731->deemph;
return 0;
static int wm8731_put_deemph(struct snd_kcontrol *kcontrol,
unsigned int deemph = ucontrol->value.integer.value[0];
if (deemph > 1)
return -EINVAL;
guard(mutex)(&wm8731->lock);
if (wm8731->deemph != deemph) {
wm8731->deemph = deemph;
wm8731_set_deemph(component);
return 1;
static const DECLARE_TLV_DB_SCALE(in_tlv, -3450, 150, 0);
static const DECLARE_TLV_DB_SCALE(sidetone_tlv, -1500, 300, 0);
static const DECLARE_TLV_DB_SCALE(out_tlv, -12100, 100, 1);
static const DECLARE_TLV_DB_SCALE(mic_tlv, 0, 2000, 0);
static const struct snd_kcontrol_new wm8731_snd_controls[] = {
SOC_DOUBLE_R_TLV("Master Playback Volume", WM8731_LOUT1V, WM8731_ROUT1V,
0, 127, 0, out_tlv),
SOC_DOUBLE_R("Master Playback ZC Switch", WM8731_LOUT1V, WM8731_ROUT1V,
7, 1, 0),
SOC_DOUBLE_R_TLV("Capture Volume", WM8731_LINVOL, WM8731_RINVOL, 0, 31, 0,
in_tlv),
SOC_DOUBLE_R("Line Capture Switch", WM8731_LINVOL, WM8731_RINVOL, 7, 1, 1),
SOC_SINGLE_TLV("Mic Boost Volume", WM8731_APANA, 0, 1, 0, mic_tlv),
SOC_SINGLE("Mic Capture Switch", WM8731_APANA, 1, 1, 1),
SOC_SINGLE_TLV("Sidetone Playback Volume", WM8731_APANA, 6, 3, 1,
sidetone_tlv),
SOC_SINGLE("ADC High Pass Filter Switch", WM8731_APDIGI, 0, 1, 1),
SOC_SINGLE("Store DC Offset Switch", WM8731_APDIGI, 4, 1, 0),
SOC_SINGLE_BOOL_EXT("Playback Deemphasis Switch", 0,
wm8731_get_deemph, wm8731_put_deemph),
/* Output Mixer */
static const struct snd_kcontrol_new wm8731_output_mixer_controls[] = {
SOC_DAPM_SINGLE("Line Bypass Switch", WM8731_APANA, 3, 1, 0),
SOC_DAPM_SINGLE("Mic Sidetone Switch", WM8731_APANA, 5, 1, 0),
SOC_DAPM_SINGLE("HiFi Playback Switch", WM8731_APANA, 4, 1, 0),
/* Input mux */
static const struct snd_kcontrol_new wm8731_input_mux_controls =
SOC_DAPM_ENUM("Input Select", wm8731_insel_enum);
static const struct snd_soc_dapm_widget wm8731_dapm_widgets[] = {
SND_SOC_DAPM_SUPPLY("ACTIVE",WM8731_ACTIVE, 0, 0, NULL, 0),
SND_SOC_DAPM_SUPPLY("OSC", WM8731_PWR, 5, 1, NULL, 0),
SND_SOC_DAPM_MIXER("Output Mixer", WM8731_PWR, 4, 1,
&wm8731_output_mixer_controls[0],
ARRAY_SIZE(wm8731_output_mixer_controls)),
SND_SOC_DAPM_DAC("DAC", "HiFi Playback", WM8731_PWR, 3, 1),
SND_SOC_DAPM_OUTPUT("LOUT"),
SND_SOC_DAPM_OUTPUT("LHPOUT"),
SND_SOC_DAPM_OUTPUT("ROUT"),
SND_SOC_DAPM_OUTPUT("RHPOUT"),
SND_SOC_DAPM_ADC("ADC", "HiFi Capture", WM8731_PWR, 2, 1),
SND_SOC_DAPM_MUX("Input Mux", SND_SOC_NOPM, 0, 0, &wm8731_input_mux_controls),
SND_SOC_DAPM_PGA("Line Input", WM8731_PWR, 0, 1, NULL, 0),
SND_SOC_DAPM_MICBIAS("Mic Bias", WM8731_PWR, 1, 1),
SND_SOC_DAPM_INPUT("MICIN"),
SND_SOC_DAPM_INPUT("RLINEIN"),
SND_SOC_DAPM_INPUT("LLINEIN"),
static int wm8731_check_osc(struct snd_soc_dapm_widget *source,
struct snd_soc_dapm_widget *sink)
struct snd_soc_component *component = snd_soc_dapm_to_component(source->dapm);
return wm8731->sysclk_type == WM8731_SYSCLK_XTAL;
static const struct snd_soc_dapm_route wm8731_intercon[] = {
{"DAC", NULL, "OSC", wm8731_check_osc},
{"ADC", NULL, "OSC", wm8731_check_osc},
{"DAC", NULL, "ACTIVE"},
{"ADC", NULL, "ACTIVE"},
/* output mixer */
{"Output Mixer", "Line Bypass Switch", "Line Input"},
{"Output Mixer", "HiFi Playback Switch", "DAC"},
{"Output Mixer", "Mic Sidetone Switch", "Mic Bias"},
/* outputs */
{"RHPOUT", NULL, "Output Mixer"},
{"ROUT", NULL, "Output Mixer"},
{"LHPOUT", NULL, "Output Mixer"},
{"LOUT", NULL, "Output Mixer"},
/* input mux */
{"Input Mux", "Line In", "Line Input"},
{"Input Mux", "Mic", "Mic Bias"},
{"ADC", NULL, "Input Mux"},
/* inputs */
{"Line Input", NULL, "LLINEIN"},
{"Line Input", NULL, "RLINEIN"},
{"Mic Bias", NULL, "MICIN"},
struct _coeff_div {
u32 mclk;
u32 rate;
u16 fs;
u8 sr:4;
u8 bosr:1;
u8 usb:1;
/* codec mclk clock divider coefficients */
static const struct _coeff_div coeff_div[] = {
/* 48k */
{12288000, 48000, 256, 0x0, 0x0, 0x0},
{18432000, 48000, 384, 0x0, 0x1, 0x0},
{12000000, 48000, 250, 0x0, 0x0, 0x1},
/* 32k */
{12288000, 32000, 384, 0x6, 0x0, 0x0},
{18432000, 32000, 576, 0x6, 0x1, 0x0},
{12000000, 32000, 375, 0x6, 0x0, 0x1},
/* 8k */
{12288000, 8000, 1536, 0x3, 0x0, 0x0},
{18432000, 8000, 2304, 0x3, 0x1, 0x0},
{11289600, 8000, 1408, 0xb, 0x0, 0x0},
{16934400, 8000, 2112, 0xb, 0x1, 0x0},
{12000000, 8000, 1500, 0x3, 0x0, 0x1},
/* 96k */
{12288000, 96000, 128, 0x7, 0x0, 0x0},
{18432000, 96000, 192, 0x7, 0x1, 0x0},
{12000000, 96000, 125, 0x7, 0x0, 0x1},
/* 44.1k */
{11289600, 44100, 256, 0x8, 0x0, 0x0},
{16934400, 44100, 384, 0x8, 0x1, 0x0},
{12000000, 44100, 272, 0x8, 0x1, 0x1},
/* 88.2k */
{11289600, 88200, 128, 0xf, 0x0, 0x0},
{16934400, 88200, 192, 0xf, 0x1, 0x0},
{12000000, 88200, 136, 0xf, 0x1, 0x1},
/* rates constraints */
static const unsigned int wm8731_rates_12000000[] = {
8000, 32000, 44100, 48000, 96000, 88200,
static const unsigned int wm8731_rates_12288000_18432000[] = {
8000, 32000, 48000, 96000,
static const unsigned int wm8731_rates_11289600_16934400[] = {
8000, 44100, 88200,
static const struct snd_pcm_hw_constraint_list wm8731_constraints_12000000 = {
.list = wm8731_rates_12000000,
.count = ARRAY_SIZE(wm8731_rates_12000000),
static const
struct snd_pcm_hw_constraint_list wm8731_constraints_12288000_18432000 = {
.list = wm8731_rates_12288000_18432000,
.count = ARRAY_SIZE(wm8731_rates_12288000_18432000),
struct snd_pcm_hw_constraint_list wm8731_constraints_11289600_16934400 = {
.list = wm8731_rates_11289600_16934400,
.count = ARRAY_SIZE(wm8731_rates_11289600_16934400),
static inline int get_coeff(int mclk, int rate)
int i;
for (i = 0; i < ARRAY_SIZE(coeff_div); i++) {
if (coeff_div[i].rate == rate && coeff_div[i].mclk == mclk)
return i;
static int wm8731_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params,
struct snd_soc_dai *dai)
struct snd_soc_component *component = dai->component;
u16 iface = snd_soc_component_read(component, WM8731_IFACE) & 0xfff3;
int i = get_coeff(wm8731->sysclk, params_rate(params));
u16 srate = (coeff_div[i].sr << 2) |
(coeff_div[i].bosr << 1) | coeff_div[i].usb;
wm8731->playback_fs = params_rate(params);
snd_soc_component_write(component, WM8731_SRATE, srate);
/* bit size */
switch (params_width(params)) {
case 16:
break;
case 20:
iface |= 0x0004;
case 24:
iface |= 0x0008;
case 32:
iface |= 0x000c;
snd_soc_component_write(component, WM8731_IFACE, iface);
static int wm8731_mute(struct snd_soc_dai *dai, int mute, int direction)
u16 mute_reg = snd_soc_component_read(component, WM8731_APDIGI) & 0xfff7;
if (mute)
snd_soc_component_write(component, WM8731_APDIGI, mute_reg | 0x8);
else
snd_soc_component_write(component, WM8731_APDIGI, mute_reg);
static int wm8731_set_dai_sysclk(struct snd_soc_dai *codec_dai,
int clk_id, unsigned int freq, int dir)
struct snd_soc_component *component = codec_dai->component;
struct snd_soc_dapm_context *dapm = snd_soc_component_to_dapm(component);
switch (clk_id) {
case WM8731_SYSCLK_XTAL:
case WM8731_SYSCLK_MCLK:
if (wm8731->mclk && clk_set_rate(wm8731->mclk, freq))
wm8731->sysclk_type = clk_id;
default:
switch (freq) {
case 0:
wm8731->constraints = NULL;
case 12000000:
wm8731->constraints = &wm8731_constraints_12000000;
case 12288000:
case 18432000:
wm8731->constraints = &wm8731_constraints_12288000_18432000;
case 16934400:
case 11289600:
wm8731->constraints = &wm8731_constraints_11289600_16934400;
wm8731->sysclk = freq;
snd_soc_dapm_sync(dapm);
static int wm8731_set_dai_fmt(struct snd_soc_dai *codec_dai,
unsigned int fmt)
u16 iface = 0;
switch (fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK) {
case SND_SOC_DAIFMT_CBP_CFP:
iface |= 0x0040;
case SND_SOC_DAIFMT_CBC_CFC:
/* interface format */
switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
case SND_SOC_DAIFMT_I2S:
iface |= 0x0002;
case SND_SOC_DAIFMT_RIGHT_J:
case SND_SOC_DAIFMT_LEFT_J:
iface |= 0x0001;
case SND_SOC_DAIFMT_DSP_A:
iface |= 0x0013;
case SND_SOC_DAIFMT_DSP_B:
iface |= 0x0003;
/* clock inversion */
switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
case SND_SOC_DAIFMT_NB_NF:
case SND_SOC_DAIFMT_IB_IF:
iface |= 0x0090;
case SND_SOC_DAIFMT_IB_NF:
iface |= 0x0080;
case SND_SOC_DAIFMT_NB_IF:
iface |= 0x0010;
/* set iface */
static int wm8731_set_bias_level(struct snd_soc_component *component,
enum snd_soc_bias_level level)
int ret;
u16 reg;
switch (level) {
case SND_SOC_BIAS_ON:
ret = clk_prepare_enable(wm8731->mclk);
if (ret)
return ret;
case SND_SOC_BIAS_PREPARE:
case SND_SOC_BIAS_STANDBY:
if (snd_soc_dapm_get_bias_level(dapm) == SND_SOC_BIAS_OFF) {
ret = regulator_bulk_enable(ARRAY_SIZE(wm8731->supplies),
wm8731->supplies);
if (ret != 0)
regcache_sync(wm8731->regmap);
/* Clear PWROFF, gate CLKOUT, everything else as-is */
reg = snd_soc_component_read(component, WM8731_PWR) & 0xff7f;
snd_soc_component_write(component, WM8731_PWR, reg | 0x0040);
case SND_SOC_BIAS_OFF:
clk_disable_unprepare(wm8731->mclk);
snd_soc_component_write(component, WM8731_PWR, 0xffff);
regulator_bulk_disable(ARRAY_SIZE(wm8731->supplies),
regcache_mark_dirty(wm8731->regmap);
static int wm8731_startup(struct snd_pcm_substream *substream,
struct wm8731_priv *wm8731 = snd_soc_component_get_drvdata(dai->component);
if (wm8731->constraints)
snd_pcm_hw_constraint_list(substream->runtime, 0,
SNDRV_PCM_HW_PARAM_RATE,
wm8731->constraints);
#define WM8731_RATES SNDRV_PCM_RATE_8000_96000
#define WM8731_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3LE |\
SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S32_LE)
static const u64 wm8731_selectable_formats =
SND_SOC_POSSIBLE_DAIFMT_I2S |
SND_SOC_POSSIBLE_DAIFMT_RIGHT_J |
SND_SOC_POSSIBLE_DAIFMT_LEFT_J |
SND_SOC_POSSIBLE_DAIFMT_DSP_A |
SND_SOC_POSSIBLE_DAIFMT_DSP_B |
SND_SOC_POSSIBLE_DAIFMT_NB_NF |
SND_SOC_POSSIBLE_DAIFMT_NB_IF |
SND_SOC_POSSIBLE_DAIFMT_IB_NF |
SND_SOC_POSSIBLE_DAIFMT_IB_IF;
static const struct snd_soc_dai_ops wm8731_dai_ops = {
.startup = wm8731_startup,
.hw_params = wm8731_hw_params,
.mute_stream = wm8731_mute,
.set_sysclk = wm8731_set_dai_sysclk,
.set_fmt = wm8731_set_dai_fmt,
.no_capture_mute = 1,
.auto_selectable_formats = &wm8731_selectable_formats,
.num_auto_selectable_formats = 1,
static struct snd_soc_dai_driver wm8731_dai = {
.name = "wm8731-hifi",
.playback = {
.stream_name = "Playback",
.channels_min = 1,
.channels_max = 2,
.rates = WM8731_RATES,
.formats = WM8731_FORMATS,},
.capture = {
.stream_name = "Capture",
.ops = &wm8731_dai_ops,
.symmetric_rate = 1,
static const struct snd_soc_component_driver soc_component_dev_wm8731 = {
.set_bias_level = wm8731_set_bias_level,
.controls = wm8731_snd_controls,
.num_controls = ARRAY_SIZE(wm8731_snd_controls),
.dapm_widgets = wm8731_dapm_widgets,
.num_dapm_widgets = ARRAY_SIZE(wm8731_dapm_widgets),
.dapm_routes = wm8731_intercon,
.num_dapm_routes = ARRAY_SIZE(wm8731_intercon),
.suspend_bias_off = 1,
.idle_bias_on = 1,
.use_pmdown_time = 1,
.endianness = 1,
int wm8731_init(struct device *dev, struct wm8731_priv *wm8731)
int ret = 0, i;
wm8731->mclk = devm_clk_get(dev, "mclk");
if (IS_ERR(wm8731->mclk)) {
ret = PTR_ERR(wm8731->mclk);
if (ret == -ENOENT) {
wm8731->mclk = NULL;
dev_warn(dev, "Assuming static MCLK\n");
dev_err(dev, "Failed to get MCLK: %d\n", ret);
mutex_init(&wm8731->lock);
for (i = 0; i < ARRAY_SIZE(wm8731->supplies); i++)
wm8731->supplies[i].supply = wm8731_supply_names[i];
ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(wm8731->supplies),
if (ret != 0) {
dev_err(dev, "Failed to request supplies: %d\n", ret);
dev_err(dev, "Failed to enable supplies: %d\n", ret);
ret = wm8731_reset(wm8731->regmap);
if (ret < 0) {
dev_err(dev, "Failed to issue reset: %d\n", ret);
goto err_regulator_enable;
/* Clear POWEROFF, keep everything else disabled */
regmap_write(wm8731->regmap, WM8731_PWR, 0x7f);
/* Latch the update bits */
regmap_update_bits(wm8731->regmap, WM8731_LOUT1V, 0x100, 0);
regmap_update_bits(wm8731->regmap, WM8731_ROUT1V, 0x100, 0);
regmap_update_bits(wm8731->regmap, WM8731_LINVOL, 0x100, 0);
regmap_update_bits(wm8731->regmap, WM8731_RINVOL, 0x100, 0);
/* Disable bypass path by default */
regmap_update_bits(wm8731->regmap, WM8731_APANA, 0x8, 0);
ret = devm_snd_soc_register_component(dev,
&soc_component_dev_wm8731, &wm8731_dai, 1);
dev_err(dev, "Failed to register CODEC: %d\n", ret);
err_regulator_enable:
/* Regulators will be enabled by bias management */
regulator_bulk_disable(ARRAY_SIZE(wm8731->supplies), wm8731->supplies);
EXPORT_SYMBOL_GPL(wm8731_init);
const struct regmap_config wm8731_regmap = {
.reg_bits = 7,
.val_bits = 9,
.max_register = WM8731_RESET,
.volatile_reg = wm8731_volatile,
.cache_type = REGCACHE_MAPLE,
.reg_defaults = wm8731_reg_defaults,
.num_reg_defaults = ARRAY_SIZE(wm8731_reg_defaults),
EXPORT_SYMBOL_GPL(wm8731_regmap);
MODULE_DESCRIPTION("ASoC WM8731 driver");
MODULE_AUTHOR("Richard Purdie");
MODULE_LICENSE("GPL");