// 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/pcm_iec958.h>
#include <sound/soc.h>
#include <sound/soc-dai.h>
#include "aiu.h"
#define AIU_958_MISC_NON_PCM BIT(0)
#define AIU_958_MISC_MODE_16BITS BIT(1)
#define AIU_958_MISC_16BITS_ALIGN GENMASK(6, 5)
#define AIU_958_MISC_MODE_32BITS BIT(7)
#define AIU_958_MISC_U_FROM_STREAM BIT(12)
#define AIU_958_MISC_FORCE_LR BIT(13)
#define AIU_958_CTRL_HOLD_EN BIT(0)
#define AIU_CLK_CTRL_958_DIV_EN BIT(1)
#define AIU_CLK_CTRL_958_DIV GENMASK(5, 4)
#define AIU_CLK_CTRL_958_DIV_MORE BIT(12)
#define AIU_CS_WORD_LEN 4
#define AIU_958_INTERNAL_DIV 2
static void
aiu_encoder_spdif_divider_enable(struct snd_soc_component *component,
bool enable)
{
snd_soc_component_update_bits(component, AIU_CLK_CTRL,
AIU_CLK_CTRL_958_DIV_EN,
enable ? AIU_CLK_CTRL_958_DIV_EN : 0);
}
static void aiu_encoder_spdif_hold(struct snd_soc_component *component,
bool enable)
{
snd_soc_component_update_bits(component, AIU_958_CTRL,
AIU_958_CTRL_HOLD_EN,
enable ? AIU_958_CTRL_HOLD_EN : 0);
}
static int
aiu_encoder_spdif_trigger(struct snd_pcm_substream *substream, int cmd,
struct snd_soc_dai *dai)
{
struct snd_soc_component *component = dai->component;
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
case SNDRV_PCM_TRIGGER_RESUME:
case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
aiu_encoder_spdif_hold(component, false);
return 0;
case SNDRV_PCM_TRIGGER_STOP:
case SNDRV_PCM_TRIGGER_SUSPEND:
case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
aiu_encoder_spdif_hold(component, true);
return 0;
default:
return -EINVAL;
}
}
static int aiu_encoder_spdif_setup_cs_word(struct snd_soc_component *component,
struct snd_pcm_hw_params *params)
{
u8 cs[AIU_CS_WORD_LEN];
unsigned int val;
int ret;
ret = snd_pcm_create_iec958_consumer_hw_params(params, cs,
AIU_CS_WORD_LEN);
if (ret < 0)
return ret;
/* Write the 1st half word */
val = cs[1] | cs[0] << 8;
snd_soc_component_write(component, AIU_958_CHSTAT_L0, val);
snd_soc_component_write(component, AIU_958_CHSTAT_R0, val);
/* Write the 2nd half word */
val = cs[3] | cs[2] << 8;
snd_soc_component_write(component, AIU_958_CHSTAT_L1, val);
snd_soc_component_write(component, AIU_958_CHSTAT_R1, val);
return 0;
}
static int aiu_encoder_spdif_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;
struct aiu *aiu = snd_soc_component_get_drvdata(component);
unsigned int val = 0, mrate;
int ret;
/* Disable the clock while changing the settings */
aiu_encoder_spdif_divider_enable(component, false);
switch (params_physical_width(params)) {
case 16:
val |= AIU_958_MISC_MODE_16BITS;
val |= FIELD_PREP(AIU_958_MISC_16BITS_ALIGN, 2);
break;
case 32:
val |= AIU_958_MISC_MODE_32BITS;
break;
default:
dev_err(dai->dev, "Unsupported physical width\n");
return -EINVAL;
}
snd_soc_component_update_bits(component, AIU_958_MISC,
AIU_958_MISC_NON_PCM |
AIU_958_MISC_MODE_16BITS |
AIU_958_MISC_16BITS_ALIGN |
AIU_958_MISC_MODE_32BITS |
AIU_958_MISC_FORCE_LR |
AIU_958_MISC_U_FROM_STREAM,
val);
/* Set the stream channel status word */
ret = aiu_encoder_spdif_setup_cs_word(component, params);
if (ret) {
dev_err(dai->dev, "failed to set channel status word\n");
return ret;
}
snd_soc_component_update_bits(component, AIU_CLK_CTRL,
AIU_CLK_CTRL_958_DIV |
AIU_CLK_CTRL_958_DIV_MORE,
FIELD_PREP(AIU_CLK_CTRL_958_DIV,
__ffs(AIU_958_INTERNAL_DIV)));
/* 2 * 32bits per subframe * 2 channels = 128 */
mrate = params_rate(params) * 128 * AIU_958_INTERNAL_DIV;
ret = clk_set_rate(aiu->spdif.clks[MCLK].clk, mrate);
if (ret) {
dev_err(dai->dev, "failed to set mclk rate\n");
return ret;
}
aiu_encoder_spdif_divider_enable(component, true);
return 0;
}
static int aiu_encoder_spdif_hw_free(struct snd_pcm_substream *substream,
struct snd_soc_dai *dai)
{
struct snd_soc_component *component = dai->component;
aiu_encoder_spdif_divider_enable(component, false);
return 0;
}
static int aiu_encoder_spdif_startup(struct snd_pcm_substream *substream,
struct snd_soc_dai *dai)
{
struct aiu *aiu = snd_soc_component_get_drvdata(dai->component);
int ret;
/*
* NOTE: Make sure the spdif block is on its own divider.
*
* The spdif can be clocked by the i2s master clock or its own
* clock. We should (in theory) change the source depending on the
* origin of the data.
*
* However, considering the clocking scheme used on these platforms,
* the master clocks will pick the same PLL source when they are
* playing from the same FIFO. The clock should be in sync so, it
* should not be necessary to reparent the spdif master clock.
*/
ret = clk_set_parent(aiu->spdif.clks[MCLK].clk,
aiu->spdif_mclk);
if (ret)
return ret;
ret = clk_bulk_prepare_enable(aiu->spdif.clk_num, aiu->spdif.clks);
if (ret)
dev_err(dai->dev, "failed to enable spdif clocks\n");
return ret;
}
static void aiu_encoder_spdif_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->spdif.clk_num, aiu->spdif.clks);
}
const struct snd_soc_dai_ops aiu_encoder_spdif_dai_ops = {
.trigger = aiu_encoder_spdif_trigger,
.hw_params = aiu_encoder_spdif_hw_params,
.hw_free = aiu_encoder_spdif_hw_free,
.startup = aiu_encoder_spdif_startup,
.shutdown = aiu_encoder_spdif_shutdown,
};
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