[PATCH] ASoC: cygnus: Add support for 384kHz frame rates

From: Lori Hikichi
Date: Mon Aug 14 2017 - 18:06:49 EST


Allow the audio ports to operate at 384kHz.

Signed-off-by: Lori Hikichi <lori.hikichi@xxxxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
sound/soc/bcm/cygnus-ssp.c | 235 +++++++++++----------------------------------
1 file changed, 55 insertions(+), 180 deletions(-)

diff --git a/sound/soc/bcm/cygnus-ssp.c b/sound/soc/bcm/cygnus-ssp.c
index e710bb0c5637..1a57a4ebc8f0 100644
--- a/sound/soc/bcm/cygnus-ssp.c
+++ b/sound/soc/bcm/cygnus-ssp.c
@@ -27,12 +27,6 @@

#define DEFAULT_VCO 1354750204

-#define CYGNUS_TDM_RATE \
- (SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_16000 | \
- SNDRV_PCM_RATE_11025 | SNDRV_PCM_RATE_22050 | \
- SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 | \
- SNDRV_PCM_RATE_48000)
-
#define CAPTURE_FCI_ID_BASE 0x180
#define CYGNUS_SSP_TRISTATE_MASK 0x001fff
#define CYGNUS_PLLCLKSEL_MASK 0xf
@@ -234,152 +228,20 @@ static const struct pll_macro_entry pll_predef_mclk[] = {
{98304000, 2},
};

+#define CYGNUS_RATE_MIN 8000
+#define CYGNUS_RATE_MAX 384000
+
/* List of valid frame sizes for tdm mode */
static const int ssp_valid_tdm_framesize[] = {32, 64, 128, 256, 512};

-/*
- * Use this relationship to derive the sampling rate (lrclk)
- * lrclk = (mclk) / ((2*mclk_to_sclk_ratio) * (32 * SCLK))).
- *
- * Use mclk and pll_ch from the table above
- *
- * Valid SCLK = 0/1/2/4/8/12
- *
- * mclk_to_sclk_ratio = number of MCLK per SCLK. Division is twice the
- * value programmed in this field.
- * Valid mclk_to_sclk_ratio = 1 through to 15
- *
- * eg: To set lrclk = 48khz, set mclk = 12288000, mclk_to_sclk_ratio = 2,
- * SCLK = 64
- */
-struct _ssp_clk_coeff {
- u32 mclk;
- u32 sclk_rate;
- u32 rate;
- u32 mclk_rate;
+static const unsigned int cygnus_rates[] = {
+ 8000, 11025, 16000, 22050, 32000, 44100, 48000,
+ 88200, 96000, 176400, 192000, 352800, 384000
};

-static const struct _ssp_clk_coeff ssp_clk_coeff[] = {
- { 4096000, 32, 16000, 4},
- { 4096000, 32, 32000, 2},
- { 4096000, 64, 8000, 4},
- { 4096000, 64, 16000, 2},
- { 4096000, 64, 32000, 1},
- { 4096000, 128, 8000, 2},
- { 4096000, 128, 16000, 1},
- { 4096000, 256, 8000, 1},
-
- { 6144000, 32, 16000, 6},
- { 6144000, 32, 32000, 3},
- { 6144000, 32, 48000, 2},
- { 6144000, 32, 96000, 1},
- { 6144000, 64, 8000, 6},
- { 6144000, 64, 16000, 3},
- { 6144000, 64, 48000, 1},
- { 6144000, 128, 8000, 3},
-
- { 8192000, 32, 32000, 4},
- { 8192000, 64, 16000, 4},
- { 8192000, 64, 32000, 2},
- { 8192000, 128, 8000, 4},
- { 8192000, 128, 16000, 2},
- { 8192000, 128, 32000, 1},
- { 8192000, 256, 8000, 2},
- { 8192000, 256, 16000, 1},
- { 8192000, 512, 8000, 1},
-
- {12288000, 32, 32000, 6},
- {12288000, 32, 48000, 4},
- {12288000, 32, 96000, 2},
- {12288000, 32, 192000, 1},
- {12288000, 64, 16000, 6},
- {12288000, 64, 32000, 3},
- {12288000, 64, 48000, 2},
- {12288000, 64, 96000, 1},
- {12288000, 128, 8000, 6},
- {12288000, 128, 16000, 3},
- {12288000, 128, 48000, 1},
- {12288000, 256, 8000, 3},
-
- {16384000, 64, 32000, 4},
- {16384000, 128, 16000, 4},
- {16384000, 128, 32000, 2},
- {16384000, 256, 8000, 4},
- {16384000, 256, 16000, 2},
- {16384000, 256, 32000, 1},
- {16384000, 512, 8000, 2},
- {16384000, 512, 16000, 1},
-
- {24576000, 32, 96000, 4},
- {24576000, 32, 192000, 2},
- {24576000, 64, 32000, 6},
- {24576000, 64, 48000, 4},
- {24576000, 64, 96000, 2},
- {24576000, 64, 192000, 1},
- {24576000, 128, 16000, 6},
- {24576000, 128, 32000, 3},
- {24576000, 128, 48000, 2},
- {24576000, 256, 8000, 6},
- {24576000, 256, 16000, 3},
- {24576000, 256, 48000, 1},
- {24576000, 512, 8000, 3},
-
- {49152000, 32, 192000, 4},
- {49152000, 64, 96000, 4},
- {49152000, 64, 192000, 2},
- {49152000, 128, 32000, 6},
- {49152000, 128, 48000, 4},
- {49152000, 128, 96000, 2},
- {49152000, 128, 192000, 1},
- {49152000, 256, 16000, 6},
- {49152000, 256, 32000, 3},
- {49152000, 256, 48000, 2},
- {49152000, 256, 96000, 1},
- {49152000, 512, 8000, 6},
- {49152000, 512, 16000, 3},
- {49152000, 512, 48000, 1},
-
- { 5644800, 32, 22050, 4},
- { 5644800, 32, 44100, 2},
- { 5644800, 32, 88200, 1},
- { 5644800, 64, 11025, 4},
- { 5644800, 64, 22050, 2},
- { 5644800, 64, 44100, 1},
-
- {11289600, 32, 44100, 4},
- {11289600, 32, 88200, 2},
- {11289600, 32, 176400, 1},
- {11289600, 64, 22050, 4},
- {11289600, 64, 44100, 2},
- {11289600, 64, 88200, 1},
- {11289600, 128, 11025, 4},
- {11289600, 128, 22050, 2},
- {11289600, 128, 44100, 1},
-
- {22579200, 32, 88200, 4},
- {22579200, 32, 176400, 2},
- {22579200, 64, 44100, 4},
- {22579200, 64, 88200, 2},
- {22579200, 64, 176400, 1},
- {22579200, 128, 22050, 4},
- {22579200, 128, 44100, 2},
- {22579200, 128, 88200, 1},
- {22579200, 256, 11025, 4},
- {22579200, 256, 22050, 2},
- {22579200, 256, 44100, 1},
-
- {45158400, 32, 176400, 4},
- {45158400, 64, 88200, 4},
- {45158400, 64, 176400, 2},
- {45158400, 128, 44100, 4},
- {45158400, 128, 88200, 2},
- {45158400, 128, 176400, 1},
- {45158400, 256, 22050, 4},
- {45158400, 256, 44100, 2},
- {45158400, 256, 88200, 1},
- {45158400, 512, 11025, 4},
- {45158400, 512, 22050, 2},
- {45158400, 512, 44100, 1},
+static const struct snd_pcm_hw_constraint_list cygnus_rate_constraint = {
+ .count = ARRAY_SIZE(cygnus_rates),
+ .list = cygnus_rates,
};

static struct cygnus_aio_port *cygnus_dai_get_portinfo(struct snd_soc_dai *dai)
@@ -679,40 +541,55 @@ static int pll_configure_mclk(struct cygnus_audio *cygaud, u32 mclk,
return p_entry->pll_ch_num;
}

-static int cygnus_ssp_set_clocks(struct cygnus_aio_port *aio,
- struct cygnus_audio *cygaud)
+static int cygnus_ssp_set_clocks(struct cygnus_aio_port *aio)
{
- u32 value, i = 0;
+ u32 value;
u32 mask = 0xf;
u32 sclk;
- bool found = false;
- const struct _ssp_clk_coeff *p_entry = NULL;
+ u32 mclk_rate;
+ unsigned int bit_rate;
+ unsigned int ratio;

- for (i = 0; i < ARRAY_SIZE(ssp_clk_coeff); i++) {
- p_entry = &ssp_clk_coeff[i];
- if ((p_entry->rate == aio->lrclk) &&
- (p_entry->sclk_rate == aio->bit_per_frame) &&
- (p_entry->mclk == aio->mclk)) {
- found = true;
- break;
- }
- }
- if (!found) {
+ bit_rate = aio->bit_per_frame * aio->lrclk;
+
+ /*
+ * Check if the bit clock can be generated from the given MCLK.
+ * MCLK must be a perfect multiple of bit clock and must be one of the
+ * following values... (2,4,6,8,10,12,14)
+ */
+ if ((aio->mclk % bit_rate) != 0)
+ return -EINVAL;
+
+ ratio = aio->mclk / bit_rate;
+ switch (ratio) {
+ case 2:
+ case 4:
+ case 6:
+ case 8:
+ case 10:
+ case 12:
+ case 14:
+ mclk_rate = ratio / 2;
+ break;
+
+ default:
dev_err(aio->cygaud->dev,
- "No valid match found in ssp_clk_coeff array\n");
+ "Invalid combination of MCLK and BCLK\n");
dev_err(aio->cygaud->dev, "lrclk = %u, bits/frame = %u, mclk = %u\n",
aio->lrclk, aio->bit_per_frame, aio->mclk);
return -EINVAL;
}

- sclk = aio->bit_per_frame;
- if (sclk == 512)
- sclk = 0;
- /* sclks_per_1fs_div = sclk cycles/32 */
- sclk /= 32;
/* Set sclk rate */
switch (aio->port_type) {
case PORT_TDM:
+ sclk = aio->bit_per_frame;
+ if (sclk == 512)
+ sclk = 0;
+
+ /* sclks_per_1fs_div = sclk cycles/32 */
+ sclk /= 32;
+
/* Set number of bitclks per frame */
value = readl(aio->cygaud->audio + aio->regs.i2s_cfg);
value &= ~(mask << I2S_OUT_CFGX_SCLKS_PER_1FS_DIV32);
@@ -731,7 +608,7 @@ static int cygnus_ssp_set_clocks(struct cygnus_aio_port *aio,
/* Set MCLK_RATE ssp port (spdif and ssp are the same) */
value = readl(aio->cygaud->audio + aio->regs.i2s_mclk_cfg);
value &= ~(0xf << I2S_OUT_MCLKRATE_SHIFT);
- value |= (p_entry->mclk_rate << I2S_OUT_MCLKRATE_SHIFT);
+ value |= (mclk_rate << I2S_OUT_MCLKRATE_SHIFT);
writel(value, aio->cygaud->audio + aio->regs.i2s_mclk_cfg);

dev_dbg(aio->cygaud->dev, "mclk cfg reg = 0x%x\n", value);
@@ -745,7 +622,6 @@ static int cygnus_ssp_hw_params(struct snd_pcm_substream *substream,
struct snd_soc_dai *dai)
{
struct cygnus_aio_port *aio = cygnus_dai_get_portinfo(dai);
- struct cygnus_audio *cygaud = snd_soc_dai_get_drvdata(dai);
int rate, bitres;
u32 value;
u32 mask = 0x1f;
@@ -841,7 +717,7 @@ static int cygnus_ssp_hw_params(struct snd_pcm_substream *substream,
aio->lrclk = rate;

if (!aio->is_slave)
- ret = cygnus_ssp_set_clocks(aio, cygaud);
+ ret = cygnus_ssp_set_clocks(aio);

return ret;
}
@@ -888,6 +764,11 @@ static int cygnus_ssp_startup(struct snd_pcm_substream *substream,
else
aio->clk_trace.cap_en = true;

+ substream->runtime->hw.rate_min = CYGNUS_RATE_MIN;
+ substream->runtime->hw.rate_max = CYGNUS_RATE_MAX;
+
+ snd_pcm_hw_constraint_list(substream->runtime, 0,
+ SNDRV_PCM_HW_PARAM_RATE, &cygnus_rate_constraint);
return 0;
}

@@ -1261,9 +1142,7 @@ static const struct snd_soc_dai_ops cygnus_ssp_dai_ops = {
.playback = { \
.channels_min = 1, \
.channels_max = 16, \
- .rates = CYGNUS_TDM_RATE | SNDRV_PCM_RATE_88200 | \
- SNDRV_PCM_RATE_96000 | SNDRV_PCM_RATE_176400 | \
- SNDRV_PCM_RATE_192000, \
+ .rates = SNDRV_PCM_RATE_KNOT, \
.formats = SNDRV_PCM_FMTBIT_S8 | \
SNDRV_PCM_FMTBIT_S16_LE | \
SNDRV_PCM_FMTBIT_S32_LE, \
@@ -1271,9 +1150,7 @@ static const struct snd_soc_dai_ops cygnus_ssp_dai_ops = {
.capture = { \
.channels_min = 2, \
.channels_max = 16, \
- .rates = CYGNUS_TDM_RATE | SNDRV_PCM_RATE_88200 | \
- SNDRV_PCM_RATE_96000 | SNDRV_PCM_RATE_176400 | \
- SNDRV_PCM_RATE_192000, \
+ .rates = SNDRV_PCM_RATE_KNOT, \
.formats = SNDRV_PCM_FMTBIT_S16_LE | \
SNDRV_PCM_FMTBIT_S32_LE, \
}, \
@@ -1293,9 +1170,7 @@ static struct snd_soc_dai_driver cygnus_spdif_dai_info = {
.playback = {
.channels_min = 2,
.channels_max = 2,
- .rates = CYGNUS_TDM_RATE | SNDRV_PCM_RATE_88200 |
- SNDRV_PCM_RATE_96000 | SNDRV_PCM_RATE_176400 |
- SNDRV_PCM_RATE_192000,
+ .rates = SNDRV_PCM_RATE_KNOT,
.formats = SNDRV_PCM_FMTBIT_S16_LE |
SNDRV_PCM_FMTBIT_S32_LE,
},
--
2.13.3