[PATCH v3 3/6] ASoC: xilinx: xlnx_i2s: Handle sysclk setting
Robert Hancock
robert.hancock at calian.com
Thu Jan 20 20:58:29 CET 2022
This driver previously only handled the set_clkdiv divider callback when
setting the SCLK Out Divider field in the I2S Timing Control register.
However, when using the simple-audio-card driver, the set_sysclk function
is called but not set_clkdiv. This caused the divider not to be set,
leaving it at an invalid value of 0 and resulting in a very low SCLK
output rate.
Handle set_clkdiv and store the sysclk (MCLK) value for later use in
hw_params to set the SCLK Out Divider such that:
MCLK/SCLK = divider * 2
Signed-off-by: Robert Hancock <robert.hancock at calian.com>
---
sound/soc/xilinx/xlnx_i2s.c | 91 +++++++++++++++++++++++++++++++++----
1 file changed, 81 insertions(+), 10 deletions(-)
diff --git a/sound/soc/xilinx/xlnx_i2s.c b/sound/soc/xilinx/xlnx_i2s.c
index 3bafa34b789a..4cc6ee7c81a3 100644
--- a/sound/soc/xilinx/xlnx_i2s.c
+++ b/sound/soc/xilinx/xlnx_i2s.c
@@ -18,6 +18,8 @@
#define DRV_NAME "xlnx_i2s"
#define I2S_CORE_CTRL_OFFSET 0x08
+#define I2S_CORE_CTRL_32BIT_LRCLK BIT(3)
+#define I2S_CORE_CTRL_ENABLE BIT(0)
#define I2S_I2STIM_OFFSET 0x20
#define I2S_CH0_OFFSET 0x30
#define I2S_I2STIM_VALID_MASK GENMASK(7, 0)
@@ -25,6 +27,12 @@
struct xlnx_i2s_drv_data {
struct snd_soc_dai_driver dai_drv;
void __iomem *base;
+ unsigned int sysclk;
+ u32 data_width;
+ u32 channels;
+ bool is_32bit_lrclk;
+ struct snd_ratnum ratnum;
+ struct snd_pcm_hw_constraint_ratnums rate_constraints;
};
static int xlnx_i2s_set_sclkout_div(struct snd_soc_dai *cpu_dai,
@@ -35,11 +43,50 @@ static int xlnx_i2s_set_sclkout_div(struct snd_soc_dai *cpu_dai,
if (!div || (div & ~I2S_I2STIM_VALID_MASK))
return -EINVAL;
+ drv_data->sysclk = 0;
+
writel(div, drv_data->base + I2S_I2STIM_OFFSET);
return 0;
}
+static int xlnx_i2s_set_sysclk(struct snd_soc_dai *dai,
+ int clk_id, unsigned int freq, int dir)
+{
+ struct xlnx_i2s_drv_data *drv_data = snd_soc_dai_get_drvdata(dai);
+
+ drv_data->sysclk = freq;
+ if (freq) {
+ unsigned int bits_per_sample;
+
+ if (drv_data->is_32bit_lrclk)
+ bits_per_sample = 32;
+ else
+ bits_per_sample = drv_data->data_width;
+
+ drv_data->ratnum.num = freq / (bits_per_sample * drv_data->channels) / 2;
+ drv_data->ratnum.den_step = 1;
+ drv_data->ratnum.den_min = 1;
+ drv_data->ratnum.den_max = 255;
+ drv_data->rate_constraints.rats = &drv_data->ratnum;
+ drv_data->rate_constraints.nrats = 1;
+ }
+ return 0;
+}
+
+static int xlnx_i2s_startup(struct snd_pcm_substream *substream,
+ struct snd_soc_dai *dai)
+{
+ struct xlnx_i2s_drv_data *drv_data = snd_soc_dai_get_drvdata(dai);
+
+ if (drv_data->sysclk)
+ return snd_pcm_hw_constraint_ratnums(substream->runtime, 0,
+ SNDRV_PCM_HW_PARAM_RATE,
+ &drv_data->rate_constraints);
+
+ return 0;
+}
+
static int xlnx_i2s_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params,
struct snd_soc_dai *i2s_dai)
@@ -47,6 +94,26 @@ static int xlnx_i2s_hw_params(struct snd_pcm_substream *substream,
u32 reg_off, chan_id;
struct xlnx_i2s_drv_data *drv_data = snd_soc_dai_get_drvdata(i2s_dai);
+ if (drv_data->sysclk) {
+ unsigned int bits_per_sample, sclk, sclk_div;
+
+ if (drv_data->is_32bit_lrclk)
+ bits_per_sample = 32;
+ else
+ bits_per_sample = drv_data->data_width;
+
+ sclk = params_rate(params) * bits_per_sample * params_channels(params);
+ sclk_div = drv_data->sysclk / sclk / 2;
+
+ if ((drv_data->sysclk % sclk != 0) ||
+ !sclk_div || (sclk_div & ~I2S_I2STIM_VALID_MASK)) {
+ dev_warn(i2s_dai->dev, "invalid SCLK divisor for sysclk %u and sclk %u\n",
+ drv_data->sysclk, sclk);
+ return -EINVAL;
+ }
+ writel(sclk_div, drv_data->base + I2S_I2STIM_OFFSET);
+ }
+
chan_id = params_channels(params) / 2;
while (chan_id > 0) {
@@ -67,7 +134,7 @@ static int xlnx_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
case SNDRV_PCM_TRIGGER_START:
case SNDRV_PCM_TRIGGER_RESUME:
case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
- writel(1, drv_data->base + I2S_CORE_CTRL_OFFSET);
+ writel(I2S_CORE_CTRL_ENABLE, drv_data->base + I2S_CORE_CTRL_OFFSET);
break;
case SNDRV_PCM_TRIGGER_STOP:
case SNDRV_PCM_TRIGGER_SUSPEND:
@@ -83,7 +150,9 @@ static int xlnx_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
static const struct snd_soc_dai_ops xlnx_i2s_dai_ops = {
.trigger = xlnx_i2s_trigger,
+ .set_sysclk = xlnx_i2s_set_sysclk,
.set_clkdiv = xlnx_i2s_set_sclkout_div,
+ .startup = xlnx_i2s_startup,
.hw_params = xlnx_i2s_hw_params
};
@@ -102,7 +171,7 @@ static int xlnx_i2s_probe(struct platform_device *pdev)
{
struct xlnx_i2s_drv_data *drv_data;
int ret;
- u32 ch, format, data_width;
+ u32 format;
struct device *dev = &pdev->dev;
struct device_node *node = dev->of_node;
@@ -114,19 +183,19 @@ static int xlnx_i2s_probe(struct platform_device *pdev)
if (IS_ERR(drv_data->base))
return PTR_ERR(drv_data->base);
- ret = of_property_read_u32(node, "xlnx,num-channels", &ch);
+ ret = of_property_read_u32(node, "xlnx,num-channels", &drv_data->channels);
if (ret < 0) {
dev_err(dev, "cannot get supported channels\n");
return ret;
}
- ch = ch * 2;
+ drv_data->channels *= 2;
- ret = of_property_read_u32(node, "xlnx,dwidth", &data_width);
+ ret = of_property_read_u32(node, "xlnx,dwidth", &drv_data->data_width);
if (ret < 0) {
dev_err(dev, "cannot get data width\n");
return ret;
}
- switch (data_width) {
+ switch (drv_data->data_width) {
case 16:
format = SNDRV_PCM_FMTBIT_S16_LE;
break;
@@ -141,21 +210,23 @@ static int xlnx_i2s_probe(struct platform_device *pdev)
drv_data->dai_drv.name = "xlnx_i2s_playback";
drv_data->dai_drv.playback.stream_name = "Playback";
drv_data->dai_drv.playback.formats = format;
- drv_data->dai_drv.playback.channels_min = ch;
- drv_data->dai_drv.playback.channels_max = ch;
+ drv_data->dai_drv.playback.channels_min = drv_data->channels;
+ drv_data->dai_drv.playback.channels_max = drv_data->channels;
drv_data->dai_drv.playback.rates = SNDRV_PCM_RATE_8000_192000;
drv_data->dai_drv.ops = &xlnx_i2s_dai_ops;
} else if (of_device_is_compatible(node, "xlnx,i2s-receiver-1.0")) {
drv_data->dai_drv.name = "xlnx_i2s_capture";
drv_data->dai_drv.capture.stream_name = "Capture";
drv_data->dai_drv.capture.formats = format;
- drv_data->dai_drv.capture.channels_min = ch;
- drv_data->dai_drv.capture.channels_max = ch;
+ drv_data->dai_drv.capture.channels_min = drv_data->channels;
+ drv_data->dai_drv.capture.channels_max = drv_data->channels;
drv_data->dai_drv.capture.rates = SNDRV_PCM_RATE_8000_192000;
drv_data->dai_drv.ops = &xlnx_i2s_dai_ops;
} else {
return -ENODEV;
}
+ drv_data->is_32bit_lrclk = readl(drv_data->base + I2S_CORE_CTRL_OFFSET) &
+ I2S_CORE_CTRL_32BIT_LRCLK;
dev_set_drvdata(&pdev->dev, drv_data);
--
2.31.1
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