// SPDX-License-Identifier: GPL-2.0
//
// Copyright (c) 2020 BayLibre, SAS.
// Author: Jerome Brunet <[email protected]>
#include <linux/bitfield.h>
#include <linux/clk.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>
#include <sound/soc-dai.h>
#include "aiu.h"
#define AIU_I2S_SOURCE_DESC_MODE_8CH BIT(0)
#define AIU_I2S_SOURCE_DESC_MODE_24BIT BIT(5)
#define AIU_I2S_SOURCE_DESC_MODE_32BIT BIT(9)
#define AIU_I2S_SOURCE_DESC_MODE_SPLIT BIT(11)
#define AIU_RST_SOFT_I2S_FAST BIT(0)
#define AIU_I2S_DAC_CFG_MSB_FIRST BIT(2)
#define AIU_CLK_CTRL_I2S_DIV_EN BIT(0)
#define AIU_CLK_CTRL_I2S_DIV GENMASK(3, 2)
#define AIU_CLK_CTRL_AOCLK_INVERT BIT(6)
#define AIU_CLK_CTRL_LRCLK_INVERT BIT(7)
#define AIU_CLK_CTRL_LRCLK_SKEW GENMASK(9, 8)
#define AIU_CLK_CTRL_MORE_HDMI_AMCLK BIT(6)
#define AIU_CLK_CTRL_MORE_I2S_DIV GENMASK(5, 0)
#define AIU_CODEC_DAC_LRCLK_CTRL_DIV GENMASK(11, 0)
static void aiu_encoder_i2s_divider_enable(struct snd_soc_component *component,
bool enable)
{
snd_soc_component_update_bits(component, AIU_CLK_CTRL,
AIU_CLK_CTRL_I2S_DIV_EN,
enable ? AIU_CLK_CTRL_I2S_DIV_EN : 0);
}
static int aiu_encoder_i2s_setup_desc(struct snd_soc_component *component,
struct snd_pcm_hw_params *params)
{
/* Always operate in split (classic interleaved) mode */
unsigned int desc = AIU_I2S_SOURCE_DESC_MODE_SPLIT;
/* Reset required to update the pipeline */
snd_soc_component_write(component, AIU_RST_SOFT, AIU_RST_SOFT_I2S_FAST);
snd_soc_component_read(component, AIU_I2S_SYNC);
switch (params_physical_width(params)) {
case 16: /* Nothing to do */
break;
case 32:
desc |= (AIU_I2S_SOURCE_DESC_MODE_24BIT |
AIU_I2S_SOURCE_DESC_MODE_32BIT);
break;
default:
return -EINVAL;
}
switch (params_channels(params)) {
case 2: /* Nothing to do */
break;
case 8:
desc |= AIU_I2S_SOURCE_DESC_MODE_8CH;
break;
default:
return -EINVAL;
}
snd_soc_component_update_bits(component, AIU_I2S_SOURCE_DESC,
AIU_I2S_SOURCE_DESC_MODE_8CH |
AIU_I2S_SOURCE_DESC_MODE_24BIT |
AIU_I2S_SOURCE_DESC_MODE_32BIT |
AIU_I2S_SOURCE_DESC_MODE_SPLIT,
desc);
return 0;
}
static int aiu_encoder_i2s_set_legacy_div(struct snd_soc_component *component,
struct snd_pcm_hw_params *params,
unsigned int bs)
{
switch (bs) {
case 1:
case 2:
case 4:
case 8:
/* These are the only valid legacy dividers */
break;
default:
dev_err(component->dev, "Unsupported i2s divider: %u\n", bs);
return -EINVAL;
}
snd_soc_component_update_bits(component, AIU_CLK_CTRL,
AIU_CLK_CTRL_I2S_DIV,
FIELD_PREP(AIU_CLK_CTRL_I2S_DIV,
__ffs(bs)));
snd_soc_component_update_bits(component, AIU_CLK_CTRL_MORE,
AIU_CLK_CTRL_MORE_I2S_DIV,
FIELD_PREP(AIU_CLK_CTRL_MORE_I2S_DIV,
0));
return 0;
}
static int aiu_encoder_i2s_set_more_div(struct snd_soc_component *component,
struct snd_pcm_hw_params *params,
unsigned int bs)
{
/*
* NOTE: this HW is odd.
* In most configuration, the i2s divider is 'mclk / blck'.
* However, in 16 bits - 8ch mode, this factor needs to be
* increased by 50% to get the correct output rate.
* No idea why !
*/
if (params_width(params) == 16 && params_channels(params) == 8) {
if (bs % 2) {
dev_err(component->dev,
"Cannot increase i2s divider by 50%%\n");
return -EINVAL;
}
bs += bs / 2;
}
/* Use CLK_MORE for mclk to bclk divider */
snd_soc_component_update_bits(component, AIU_CLK_CTRL,
AIU_CLK_CTRL_I2S_DIV,
FIELD_PREP(AIU_CLK_CTRL_I2S_DIV, 0));
snd_soc_component_update_bits(component, AIU_CLK_CTRL_MORE,
AIU_CLK_CTRL_MORE_I2S_DIV,
FIELD_PREP(AIU_CLK_CTRL_MORE_I2S_DIV,
bs - 1));
return 0;
}
static int aiu_encoder_i2s_set_clocks(struct snd_soc_component *component,
struct snd_pcm_hw_params *params)
{
struct aiu *aiu = snd_soc_component_get_drvdata(component);
unsigned int srate = params_rate(params);
unsigned int fs, bs;
int ret;
/* Get the oversampling factor */
fs = DIV_ROUND_CLOSEST(clk_get_rate(aiu->i2s.clks[MCLK].clk), srate);
if (fs % 64)
return -EINVAL;
/* Send data MSB first */
snd_soc_component_update_bits(component, AIU_I2S_DAC_CFG,
AIU_I2S_DAC_CFG_MSB_FIRST,
AIU_I2S_DAC_CFG_MSB_FIRST);
/* Set bclk to lrlck ratio */
snd_soc_component_update_bits(component, AIU_CODEC_DAC_LRCLK_CTRL,
AIU_CODEC_DAC_LRCLK_CTRL_DIV,
FIELD_PREP(AIU_CODEC_DAC_LRCLK_CTRL_DIV,
64 - 1));
bs = fs / 64;
if (aiu->platform->has_clk_ctrl_more_i2s_div)
ret = aiu_encoder_i2s_set_more_div(component, params, bs);
else
ret = aiu_encoder_i2s_set_legacy_div(component, params, bs);
if (ret)
return ret;
/* Make sure amclk is used for HDMI i2s as well */
snd_soc_component_update_bits(component, AIU_CLK_CTRL_MORE,
AIU_CLK_CTRL_MORE_HDMI_AMCLK,
AIU_CLK_CTRL_MORE_HDMI_AMCLK);
return 0;
}
static int aiu_encoder_i2s_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;
int ret;
/* Disable the clock while changing the settings */
aiu_encoder_i2s_divider_enable(component, false);
ret = aiu_encoder_i2s_setup_desc(component, params);
if (ret) {
dev_err(dai->dev, "setting i2s desc failed\n");
return ret;
}
ret = aiu_encoder_i2s_set_clocks(component, params);
if (ret) {
dev_err(dai->dev, "setting i2s clocks failed\n");
return ret;
}
aiu_encoder_i2s_divider_enable(component, true);
return 0;
}
static int aiu_encoder_i2s_hw_free(struct snd_pcm_substream *substream,
struct snd_soc_dai *dai)
{
struct snd_soc_component *component = dai->component;
aiu_encoder_i2s_divider_enable(component, false);
return 0;
}
static int aiu_encoder_i2s_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
{
struct snd_soc_component *component = dai->component;
unsigned int inv = fmt & SND_SOC_DAIFMT_INV_MASK;
unsigned int val = 0;
unsigned int skew;
/* Only CPU Master / Codec Slave supported ATM */
if ((fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK) != SND_SOC_DAIFMT_BP_FP)
return -EINVAL;
if (inv == SND_SOC_DAIFMT_NB_IF ||
inv == SND_SOC_DAIFMT_IB_IF)
val |= AIU_CLK_CTRL_LRCLK_INVERT;
if (inv == SND_SOC_DAIFMT_IB_NF ||
inv == SND_SOC_DAIFMT_IB_IF)
val |= AIU_CLK_CTRL_AOCLK_INVERT;
/* Signal skew */
switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
case SND_SOC_DAIFMT_I2S:
/* Invert sample clock for i2s */
val ^= AIU_CLK_CTRL_LRCLK_INVERT;
skew = 1;
break;
case SND_SOC_DAIFMT_LEFT_J:
skew = 0;
break;
default:
return -EINVAL;
}
val |= FIELD_PREP(AIU_CLK_CTRL_LRCLK_SKEW, skew);
snd_soc_component_update_bits(component, AIU_CLK_CTRL,
AIU_CLK_CTRL_LRCLK_INVERT |
AIU_CLK_CTRL_AOCLK_INVERT |
AIU_CLK_CTRL_LRCLK_SKEW,
val);
return 0;
}
static int aiu_encoder_i2s_set_sysclk(struct snd_soc_dai *dai, int clk_id,
unsigned int freq, int dir)
{
struct aiu *aiu = snd_soc_component_get_drvdata(dai->component);
int ret;
if (WARN_ON(clk_id != 0))
return -EINVAL;
if (dir == SND_SOC_CLOCK_IN)
return 0;
ret = clk_set_rate(aiu->i2s.clks[MCLK].clk, freq);
if (ret)
dev_err(dai->dev, "Failed to set sysclk to %uHz", freq);
return ret;
}
static const unsigned int hw_channels[] = {2, 8};
static const struct snd_pcm_hw_constraint_list hw_channel_constraints = {
.list = hw_channels,
.count = ARRAY_SIZE(hw_channels),
.mask = 0,
};
static int aiu_encoder_i2s_startup(struct snd_pcm_substream *substream,
struct snd_soc_dai *dai)
{
struct aiu *aiu = snd_soc_component_get_drvdata(dai->component);
int ret;
/* Make sure the encoder gets either 2 or 8 channels */
ret = snd_pcm_hw_constraint_list(substream->runtime, 0,
SNDRV_PCM_HW_PARAM_CHANNELS,
&hw_channel_constraints);
if (ret) {
dev_err(dai->dev, "adding channels constraints failed\n");
return ret;
}
ret = clk_bulk_prepare_enable(aiu->i2s.clk_num, aiu->i2s.clks);
if (ret)
dev_err(dai->dev, "failed to enable i2s clocks\n");
return ret;
}
static void aiu_encoder_i2s_shutdown(struct snd_pcm_substream *substream,
struct snd_soc_dai *dai)
{
struct aiu *aiu = snd_soc_component_get_drvdata(dai->component);
clk_bulk_disable_unprepare(aiu->i2s.clk_num, aiu->i2s.clks);
}
const struct snd_soc_dai_ops aiu_encoder_i2s_dai_ops = {
.hw_params = aiu_encoder_i2s_hw_params,
.hw_free = aiu_encoder_i2s_hw_free,
.set_fmt = aiu_encoder_i2s_set_fmt,
.set_sysclk = aiu_encoder_i2s_set_sysclk,
.startup = aiu_encoder_i2s_startup,
.shutdown = aiu_encoder_i2s_shutdown,
};
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