ASoC: fsl_sai: add sai master mode support

When sai works on master mode, set its bit clock and frame clock.

SAI has 4 MCLK source, bus clock, MCLK1, MCLK2 and MCLK3. fsl_sai_set_bclk
will select proper MCLK source, then calculate and set the bit clock divider.

After fsl_sai_set_bclk, enable the selected mclk in hw_params(), and add
hw_free() to disable the mclk.

Signed-off-by: Zidan Wang <zidan.wang@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Zidan Wang 2015-05-11 18:24:41 +08:00 committed by Mark Brown
parent b787f68c36
commit c3ecef21c3
2 changed files with 121 additions and 5 deletions

View File

@ -1,7 +1,7 @@
/*
* Freescale ALSA SoC Digital Audio Interface (SAI) driver.
*
* Copyright 2012-2013 Freescale Semiconductor, Inc.
* Copyright 2012-2015 Freescale Semiconductor, Inc.
*
* This program is free software, you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
@ -251,12 +251,14 @@ static int fsl_sai_set_dai_fmt_tr(struct snd_soc_dai *cpu_dai,
val_cr4 |= FSL_SAI_CR4_FSD_MSTR;
break;
case SND_SOC_DAIFMT_CBM_CFM:
sai->is_slave_mode = true;
break;
case SND_SOC_DAIFMT_CBS_CFM:
val_cr2 |= FSL_SAI_CR2_BCD_MSTR;
break;
case SND_SOC_DAIFMT_CBM_CFS:
val_cr4 |= FSL_SAI_CR4_FSD_MSTR;
sai->is_slave_mode = true;
break;
default:
return -EINVAL;
@ -288,6 +290,79 @@ static int fsl_sai_set_dai_fmt(struct snd_soc_dai *cpu_dai, unsigned int fmt)
return ret;
}
static int fsl_sai_set_bclk(struct snd_soc_dai *dai, bool tx, u32 freq)
{
struct fsl_sai *sai = snd_soc_dai_get_drvdata(dai);
unsigned long clk_rate;
u32 savediv = 0, ratio, savesub = freq;
u32 id;
int ret = 0;
/* Don't apply to slave mode */
if (sai->is_slave_mode)
return 0;
for (id = 0; id < FSL_SAI_MCLK_MAX; id++) {
clk_rate = clk_get_rate(sai->mclk_clk[id]);
if (!clk_rate)
continue;
ratio = clk_rate / freq;
ret = clk_rate - ratio * freq;
/*
* Drop the source that can not be
* divided into the required rate.
*/
if (ret != 0 && clk_rate / ret < 1000)
continue;
dev_dbg(dai->dev,
"ratio %d for freq %dHz based on clock %ldHz\n",
ratio, freq, clk_rate);
if (ratio % 2 == 0 && ratio >= 2 && ratio <= 512)
ratio /= 2;
else
continue;
if (ret < savesub) {
savediv = ratio;
sai->mclk_id[tx] = id;
savesub = ret;
}
if (ret == 0)
break;
}
if (savediv == 0) {
dev_err(dai->dev, "failed to derive required %cx rate: %d\n",
tx ? 'T' : 'R', freq);
return -EINVAL;
}
if ((tx && sai->synchronous[TX]) || (!tx && !sai->synchronous[RX])) {
regmap_update_bits(sai->regmap, FSL_SAI_RCR2,
FSL_SAI_CR2_MSEL_MASK,
FSL_SAI_CR2_MSEL(sai->mclk_id[tx]));
regmap_update_bits(sai->regmap, FSL_SAI_RCR2,
FSL_SAI_CR2_DIV_MASK, savediv - 1);
} else {
regmap_update_bits(sai->regmap, FSL_SAI_TCR2,
FSL_SAI_CR2_MSEL_MASK,
FSL_SAI_CR2_MSEL(sai->mclk_id[tx]));
regmap_update_bits(sai->regmap, FSL_SAI_TCR2,
FSL_SAI_CR2_DIV_MASK, savediv - 1);
}
dev_dbg(dai->dev, "best fit: clock id=%d, div=%d, deviation =%d\n",
sai->mclk_id[tx], savediv, savesub);
return 0;
}
static int fsl_sai_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params,
struct snd_soc_dai *cpu_dai)
@ -297,6 +372,24 @@ static int fsl_sai_hw_params(struct snd_pcm_substream *substream,
unsigned int channels = params_channels(params);
u32 word_width = snd_pcm_format_width(params_format(params));
u32 val_cr4 = 0, val_cr5 = 0;
int ret;
if (!sai->is_slave_mode) {
ret = fsl_sai_set_bclk(cpu_dai, tx,
2 * word_width * params_rate(params));
if (ret)
return ret;
/* Do not enable the clock if it is already enabled */
if (!(sai->mclk_streams & BIT(substream->stream))) {
ret = clk_prepare_enable(sai->mclk_clk[sai->mclk_id[tx]]);
if (ret)
return ret;
sai->mclk_streams |= BIT(substream->stream);
}
}
if (!sai->is_dsp_mode)
val_cr4 |= FSL_SAI_CR4_SYWD(word_width);
@ -322,6 +415,22 @@ static int fsl_sai_hw_params(struct snd_pcm_substream *substream,
return 0;
}
static int fsl_sai_hw_free(struct snd_pcm_substream *substream,
struct snd_soc_dai *cpu_dai)
{
struct fsl_sai *sai = snd_soc_dai_get_drvdata(cpu_dai);
bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
if (!sai->is_slave_mode &&
sai->mclk_streams & BIT(substream->stream)) {
clk_disable_unprepare(sai->mclk_clk[sai->mclk_id[tx]]);
sai->mclk_streams &= ~BIT(substream->stream);
}
return 0;
}
static int fsl_sai_trigger(struct snd_pcm_substream *substream, int cmd,
struct snd_soc_dai *cpu_dai)
{
@ -428,6 +537,7 @@ static const struct snd_soc_dai_ops fsl_sai_pcm_dai_ops = {
.set_sysclk = fsl_sai_set_dai_sysclk,
.set_fmt = fsl_sai_set_dai_fmt,
.hw_params = fsl_sai_hw_params,
.hw_free = fsl_sai_hw_free,
.trigger = fsl_sai_trigger,
.startup = fsl_sai_startup,
.shutdown = fsl_sai_shutdown,
@ -600,8 +710,9 @@ static int fsl_sai_probe(struct platform_device *pdev)
sai->bus_clk = NULL;
}
for (i = 0; i < FSL_SAI_MCLK_MAX; i++) {
sprintf(tmp, "mclk%d", i + 1);
sai->mclk_clk[0] = sai->bus_clk;
for (i = 1; i < FSL_SAI_MCLK_MAX; i++) {
sprintf(tmp, "mclk%d", i);
sai->mclk_clk[i] = devm_clk_get(&pdev->dev, tmp);
if (IS_ERR(sai->mclk_clk[i])) {
dev_err(&pdev->dev, "failed to get mclk%d clock: %ld\n",

View File

@ -72,13 +72,15 @@
/* SAI Transmit and Recieve Configuration 2 Register */
#define FSL_SAI_CR2_SYNC BIT(30)
#define FSL_SAI_CR2_MSEL_MASK (0xff << 26)
#define FSL_SAI_CR2_MSEL_MASK (0x3 << 26)
#define FSL_SAI_CR2_MSEL_BUS 0
#define FSL_SAI_CR2_MSEL_MCLK1 BIT(26)
#define FSL_SAI_CR2_MSEL_MCLK2 BIT(27)
#define FSL_SAI_CR2_MSEL_MCLK3 (BIT(26) | BIT(27))
#define FSL_SAI_CR2_MSEL(ID) ((ID) << 26)
#define FSL_SAI_CR2_BCP BIT(25)
#define FSL_SAI_CR2_BCD_MSTR BIT(24)
#define FSL_SAI_CR2_DIV_MASK 0xff
/* SAI Transmit and Recieve Configuration 3 Register */
#define FSL_SAI_CR3_TRCE BIT(16)
@ -120,7 +122,7 @@
#define FSL_SAI_CLK_MAST2 2
#define FSL_SAI_CLK_MAST3 3
#define FSL_SAI_MCLK_MAX 3
#define FSL_SAI_MCLK_MAX 4
/* SAI data transfer numbers per DMA request */
#define FSL_SAI_MAXBURST_TX 6
@ -132,11 +134,14 @@ struct fsl_sai {
struct clk *bus_clk;
struct clk *mclk_clk[FSL_SAI_MCLK_MAX];
bool is_slave_mode;
bool is_lsb_first;
bool is_dsp_mode;
bool sai_on_imx;
bool synchronous[2];
unsigned int mclk_id[2];
unsigned int mclk_streams;
struct snd_dmaengine_dai_dma_data dma_params_rx;
struct snd_dmaengine_dai_dma_data dma_params_tx;
};