[PATCH 2/3 v2] ASoC: dwc: Add I2S HDMI audio support

From: Jose Abreu
Date: Mon Mar 28 2016 - 10:37:23 EST


HDMI audio support was added to the AXS board using an
I2S cpu driver and a custom platform driver.

The platform driver supports two channels @ 16 bits with
rates 32k, 44.1k and 48k. ALSA Simple audio card is used to
glue the cpu, platform and codec driver (adv7511).

Signed-off-by: Jose Abreu <joabreu@xxxxxxxxxxxx>
---

No changes v1 -> v2.

sound/soc/dwc/Kconfig | 1 +
sound/soc/dwc/designware_i2s.c | 385 +++++++++++++++++++++++++++++++++++++++--
2 files changed, 373 insertions(+), 13 deletions(-)

diff --git a/sound/soc/dwc/Kconfig b/sound/soc/dwc/Kconfig
index d50e085..bc3fae7 100644
--- a/sound/soc/dwc/Kconfig
+++ b/sound/soc/dwc/Kconfig
@@ -2,6 +2,7 @@ config SND_DESIGNWARE_I2S
tristate "Synopsys I2S Device Driver"
depends on CLKDEV_LOOKUP
select SND_SOC_GENERIC_DMAENGINE_PCM
+ select SND_SIMPLE_CARD
help
Say Y or M if you want to add support for I2S driver for
Synopsys desigwnware I2S device. The device supports upto
diff --git a/sound/soc/dwc/designware_i2s.c b/sound/soc/dwc/designware_i2s.c
index bff258d..0f2f588 100644
--- a/sound/soc/dwc/designware_i2s.c
+++ b/sound/soc/dwc/designware_i2s.c
@@ -84,11 +84,37 @@
#define MAX_CHANNEL_NUM 8
#define MIN_CHANNEL_NUM 2

+/* FPGA Version Info */
+#define FPGA_VER_INFO 0xE0011230
+#define FPGA_VER_27M 0x000FBED9
+
+/* PLL registers addresses */
+#define PLL_IDIV_ADDR 0xE00100A0
+#define PLL_FBDIV_ADDR 0xE00100A4
+#define PLL_ODIV0_ADDR 0xE00100A8
+#define PLL_ODIV1_ADDR 0xE00100AC
+
+/* PCM definitions */
+#define BUFFER_BYTES_MAX 384000
+#define PERIOD_BYTES_MIN 2048
+#define PERIODS_MIN 8
+
union dw_i2s_snd_dma_data {
struct i2s_dma_data pd;
struct snd_dmaengine_dai_dma_data dt;
};

+struct dw_pcm_binfo {
+ struct snd_pcm_substream *stream;
+ unsigned char *dma_base;
+ unsigned char *dma_pointer;
+ unsigned int period_size_frames;
+ unsigned int size;
+ snd_pcm_uframes_t period_pointer;
+ unsigned int total_periods;
+ unsigned int current_period;
+};
+
struct dw_i2s_dev {
void __iomem *i2s_base;
struct clk *clk;
@@ -100,14 +126,103 @@ struct dw_i2s_dev {
struct device *dev;
u32 ccr;
u32 xfer_resolution;
+ u32 xfer_bytes;
+ u32 fifo_th;

/* data related to DMA transfers b/w i2s and DMAC */
union dw_i2s_snd_dma_data play_dma_data;
union dw_i2s_snd_dma_data capture_dma_data;
struct i2s_clk_config_data config;
int (*i2s_clk_cfg)(struct i2s_clk_config_data *config);
+ struct dw_pcm_binfo binfo;
+};
+
+struct dw_i2s_pll {
+ unsigned int rate;
+ unsigned int data_width;
+ unsigned int idiv;
+ unsigned int fbdiv;
+ unsigned int odiv0;
+ unsigned int odiv1;
+};
+
+static const struct dw_i2s_pll dw_i2s_pll_cfg_27m[] = {
+ /* 27Mhz */
+ { 32000, 16, 0x104, 0x451, 0x10E38, 0x2000 },
+ { 44100, 16, 0x104, 0x596, 0x10D35, 0x2000 },
+ { 48000, 16, 0x208, 0xA28, 0x10B2C, 0x2000 },
+ { 0, 0, 0, 0, 0, 0 },
};

+static const struct dw_i2s_pll dw_i2s_pll_cfg_28m[] = {
+ /* 28.224Mhz */
+ { 32000, 16, 0x82, 0x105, 0x107DF, 0x2000 },
+ { 44100, 16, 0x28A, 0x1, 0x10001, 0x2000 },
+ { 48000, 16, 0xA28, 0x187, 0x10042, 0x2000 },
+ { 0, 0, 0, 0, 0, 0 },
+};
+
+static const struct snd_pcm_hardware dw_pcm_hw = {
+ .info = SNDRV_PCM_INFO_INTERLEAVED |
+ SNDRV_PCM_INFO_MMAP |
+ SNDRV_PCM_INFO_MMAP_VALID |
+ SNDRV_PCM_INFO_BLOCK_TRANSFER,
+ .rates = SNDRV_PCM_RATE_32000 |
+ SNDRV_PCM_RATE_44100 |
+ SNDRV_PCM_RATE_48000,
+ .rate_min = 32000,
+ .rate_max = 48000,
+ .formats = SNDRV_PCM_FMTBIT_S16_LE,
+ .channels_min = 2,
+ .channels_max = 2,
+ .buffer_bytes_max = BUFFER_BYTES_MAX,
+ .period_bytes_min = PERIOD_BYTES_MIN,
+ .period_bytes_max = BUFFER_BYTES_MAX / PERIODS_MIN,
+ .periods_min = PERIODS_MIN,
+ .periods_max = BUFFER_BYTES_MAX / PERIOD_BYTES_MIN,
+};
+
+static int dw_pcm_transfer(u32 *lsample, u32 *rsample, int bytes, int buf_size,
+ struct dw_pcm_binfo *bi)
+{
+ struct snd_pcm_runtime *rt = NULL;
+ int i;
+
+ if (!bi)
+ return -EINVAL;
+
+ rt = bi->stream->runtime;
+
+ for (i = 0; i < buf_size; i++) {
+ if (bi->stream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+ memcpy(&lsample[i], bi->dma_pointer, bytes);
+ bi->dma_pointer += bytes;
+ memcpy(&rsample[i], bi->dma_pointer, bytes);
+ bi->dma_pointer += bytes;
+ } else {
+ memcpy(bi->dma_pointer, &lsample[i], bytes);
+ bi->dma_pointer += bytes;
+ memcpy(bi->dma_pointer, &rsample[i], bytes);
+ bi->dma_pointer += bytes;
+ }
+ }
+ bi->period_pointer += bytes_to_frames(rt, bytes * 2 * buf_size);
+
+ if (bi->period_pointer >=
+ (bi->period_size_frames * bi->current_period)) {
+ bi->current_period++;
+ if (bi->current_period > bi->total_periods) {
+ bi->dma_pointer = bi->dma_base;
+ bi->period_pointer = 0;
+ bi->current_period = 1;
+ }
+
+ snd_pcm_period_elapsed(bi->stream);
+ }
+
+ return 0;
+}
+
static inline void i2s_write_reg(void __iomem *io_base, int reg, u32 val)
{
writel(val, io_base + reg);
@@ -144,20 +259,94 @@ static inline void i2s_clear_irqs(struct dw_i2s_dev *dev, u32 stream)
}
}

+static irqreturn_t i2s_irq_handler(int irq, void *dev_id)
+{
+ struct dw_i2s_dev *dev = dev_id;
+ u32 isr[4], sleft[dev->fifo_th], sright[dev->fifo_th];
+ int i, j;
+
+ for (i = 0; i < 4; i++)
+ isr[i] = i2s_read_reg(dev->i2s_base, ISR(i));
+
+ for (i = 0; i < 4; i++) {
+ /* Copy only to/from first two channels.
+ * TODO: Remaining channels
+ */
+ if ((isr[i] & 0x10) && (i == 0) && (dev->binfo.stream->stream ==
+ SNDRV_PCM_STREAM_PLAYBACK)) {
+ /* TXFE - TX FIFO is empty */
+ dw_pcm_transfer(sleft, sright, dev->xfer_bytes,
+ dev->fifo_th, &dev->binfo);
+
+ for (j = 0; j < dev->fifo_th; j++) {
+ i2s_write_reg(dev->i2s_base, LRBR_LTHR(i),
+ sleft[j]);
+ i2s_write_reg(dev->i2s_base, RRBR_RTHR(i),
+ sright[j]);
+ }
+ } else if ((isr[i] & 0x1) && (i == 0) &&
+ (dev->binfo.stream->stream ==
+ SNDRV_PCM_STREAM_CAPTURE)) {
+ /* RSFE - RX FIFO is full */
+ for (j = 0; j < dev->fifo_th; j++) {
+ sleft[j] = i2s_read_reg(dev->i2s_base,
+ LRBR_LTHR(i));
+ sright[j] = i2s_read_reg(dev->i2s_base,
+ RRBR_RTHR(i));
+ }
+
+ dw_pcm_transfer(sleft, sright, dev->xfer_bytes,
+ dev->fifo_th, &dev->binfo);
+ }
+ }
+
+ i2s_clear_irqs(dev, SNDRV_PCM_STREAM_PLAYBACK);
+ i2s_clear_irqs(dev, SNDRV_PCM_STREAM_CAPTURE);
+
+ return IRQ_HANDLED;
+}
+
+static int i2s_pll_cfg(struct i2s_clk_config_data *config)
+{
+ const struct dw_i2s_pll *pll_cfg;
+ u32 rate = config->sample_rate;
+ u32 data_width = config->data_width;
+ int i;
+
+ if (readl((void *)FPGA_VER_INFO) <= FPGA_VER_27M)
+ pll_cfg = dw_i2s_pll_cfg_27m;
+ else
+ pll_cfg = dw_i2s_pll_cfg_28m;
+
+ for (i = 0; pll_cfg[i].rate != 0; i++) {
+ if ((pll_cfg[i].rate == rate) &&
+ (pll_cfg[i].data_width == data_width)) {
+ writel(pll_cfg[i].idiv, (void *)PLL_IDIV_ADDR);
+ writel(pll_cfg[i].fbdiv, (void *)PLL_FBDIV_ADDR);
+ writel(pll_cfg[i].odiv0, (void *)PLL_ODIV0_ADDR);
+ writel(pll_cfg[i].odiv1, (void *)PLL_ODIV1_ADDR);
+ return 0;
+ }
+ }
+
+ return -EINVAL;
+}
+
static void i2s_start(struct dw_i2s_dev *dev,
struct snd_pcm_substream *substream)
{
+ struct i2s_clk_config_data *config = &dev->config;
u32 i, irq;
i2s_write_reg(dev->i2s_base, IER, 1);

if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
- for (i = 0; i < 4; i++) {
+ for (i = 0; i < (config->chan_nr / 2); i++) {
irq = i2s_read_reg(dev->i2s_base, IMR(i));
i2s_write_reg(dev->i2s_base, IMR(i), irq & ~0x30);
}
i2s_write_reg(dev->i2s_base, ITER, 1);
} else {
- for (i = 0; i < 4; i++) {
+ for (i = 0; i < (config->chan_nr / 2); i++) {
irq = i2s_read_reg(dev->i2s_base, IMR(i));
i2s_write_reg(dev->i2s_base, IMR(i), irq & ~0x03);
}
@@ -195,6 +384,139 @@ static void i2s_stop(struct dw_i2s_dev *dev,
}
}

+static int dw_pcm_open(struct snd_pcm_substream *substream)
+{
+ struct snd_soc_pcm_runtime *rtd = substream->private_data;
+ struct snd_pcm_runtime *rt = substream->runtime;
+ struct dw_i2s_dev *dev = snd_soc_dai_get_drvdata(rtd->cpu_dai);
+
+ snd_soc_set_runtime_hwparams(substream, &dw_pcm_hw);
+ snd_pcm_hw_constraint_integer(rt, SNDRV_PCM_HW_PARAM_PERIODS);
+
+ rt->hw.rate_min = 32000;
+ rt->hw.rate_max = 48000;
+
+ dev->binfo.stream = substream;
+ rt->private_data = &dev->binfo;
+ return 0;
+}
+
+static int dw_pcm_close(struct snd_pcm_substream *substream)
+{
+ return 0;
+}
+
+static int dw_pcm_hw_params(struct snd_pcm_substream *substream,
+ struct snd_pcm_hw_params *hw_params)
+{
+ struct snd_pcm_runtime *rt = substream->runtime;
+ struct dw_pcm_binfo *bi = rt->private_data;
+ int ret;
+
+ ret = snd_pcm_lib_alloc_vmalloc_buffer(substream,
+ params_buffer_bytes(hw_params));
+ if (ret < 0)
+ return ret;
+
+ memset(rt->dma_area, 0, params_buffer_bytes(hw_params));
+ bi->dma_base = rt->dma_area;
+ bi->dma_pointer = bi->dma_base;
+
+ return 0;
+}
+
+static int dw_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+ int ret;
+
+ ret = snd_pcm_lib_free_vmalloc_buffer(substream);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int dw_pcm_prepare(struct snd_pcm_substream *substream)
+{
+ struct snd_pcm_runtime *rt = substream->runtime;
+ struct dw_pcm_binfo *bi = rt->private_data;
+ u32 buffer_size_frames = 0;
+
+ bi->period_size_frames = bytes_to_frames(rt,
+ snd_pcm_lib_period_bytes(substream));
+ bi->size = snd_pcm_lib_buffer_bytes(substream);
+ buffer_size_frames = bytes_to_frames(rt, bi->size);
+ bi->total_periods = buffer_size_frames / bi->period_size_frames;
+ bi->current_period = 1;
+
+ if ((buffer_size_frames % bi->period_size_frames) != 0)
+ return -EINVAL;
+
+ return 0;
+}
+
+static int dw_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+ switch (cmd) {
+ case SNDRV_PCM_TRIGGER_START:
+ break;
+ case SNDRV_PCM_TRIGGER_STOP:
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static snd_pcm_uframes_t dw_pcm_pointer(struct snd_pcm_substream *substream)
+{
+ struct snd_pcm_runtime *rt = substream->runtime;
+ struct dw_pcm_binfo *bi = rt->private_data;
+
+ return bi->period_pointer;
+}
+
+static struct snd_pcm_ops dw_pcm_ops = {
+ .open = dw_pcm_open,
+ .close = dw_pcm_close,
+ .ioctl = snd_pcm_lib_ioctl,
+ .hw_params = dw_pcm_hw_params,
+ .hw_free = dw_pcm_hw_free,
+ .prepare = dw_pcm_prepare,
+ .trigger = dw_pcm_trigger,
+ .pointer = dw_pcm_pointer,
+ .page = snd_pcm_lib_get_vmalloc_page,
+ .mmap = snd_pcm_lib_mmap_vmalloc,
+};
+
+static int dw_pcm_new(struct snd_soc_pcm_runtime *runtime)
+{
+ struct snd_pcm *pcm = runtime->pcm;
+ int ret;
+
+ ret = snd_pcm_lib_preallocate_pages_for_all(pcm,
+ SNDRV_DMA_TYPE_DEV,
+ snd_dma_continuous_data(GFP_KERNEL),
+ dw_pcm_hw.buffer_bytes_max,
+ dw_pcm_hw.buffer_bytes_max);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static void dw_pcm_free(struct snd_pcm *pcm)
+{
+ snd_pcm_lib_preallocate_free_for_all(pcm);
+}
+
+static struct snd_soc_platform_driver dw_pcm_soc_platform = {
+ .pcm_new = dw_pcm_new,
+ .pcm_free = dw_pcm_free,
+ .ops = &dw_pcm_ops,
+};
+
static int dw_i2s_startup(struct snd_pcm_substream *substream,
struct snd_soc_dai *cpu_dai)
{
@@ -231,14 +553,16 @@ static void dw_i2s_config(struct dw_i2s_dev *dev, int stream)
if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
i2s_write_reg(dev->i2s_base, TCR(ch_reg),
dev->xfer_resolution);
- i2s_write_reg(dev->i2s_base, TFCR(ch_reg), 0x02);
+ i2s_write_reg(dev->i2s_base, TFCR(ch_reg),
+ dev->fifo_th - 1);
irq = i2s_read_reg(dev->i2s_base, IMR(ch_reg));
i2s_write_reg(dev->i2s_base, IMR(ch_reg), irq & ~0x30);
i2s_write_reg(dev->i2s_base, TER(ch_reg), 1);
} else {
i2s_write_reg(dev->i2s_base, RCR(ch_reg),
dev->xfer_resolution);
- i2s_write_reg(dev->i2s_base, RFCR(ch_reg), 0x07);
+ i2s_write_reg(dev->i2s_base, RFCR(ch_reg),
+ dev->fifo_th - 1);
irq = i2s_read_reg(dev->i2s_base, IMR(ch_reg));
i2s_write_reg(dev->i2s_base, IMR(ch_reg), irq & ~0x03);
i2s_write_reg(dev->i2s_base, RER(ch_reg), 1);
@@ -259,22 +583,25 @@ static int dw_i2s_hw_params(struct snd_pcm_substream *substream,
config->data_width = 16;
dev->ccr = 0x00;
dev->xfer_resolution = 0x02;
+ dev->xfer_bytes = 0x02;
break;

case SNDRV_PCM_FORMAT_S24_LE:
config->data_width = 24;
dev->ccr = 0x08;
dev->xfer_resolution = 0x04;
+ dev->xfer_bytes = 0x03;
break;

case SNDRV_PCM_FORMAT_S32_LE:
config->data_width = 32;
dev->ccr = 0x10;
dev->xfer_resolution = 0x05;
+ dev->xfer_bytes = 0x04;
break;

default:
- dev_err(dev->dev, "designware-i2s: unsuppted PCM fmt");
+ dev_err(dev->dev, "designware-i2s: unsupported PCM fmt");
return -EINVAL;
}

@@ -316,6 +643,7 @@ static int dw_i2s_hw_params(struct snd_pcm_substream *substream,
}
}
}
+
return 0;
}

@@ -498,6 +826,7 @@ static int dw_configure_dai(struct dw_i2s_dev *dev,
*/
u32 comp1 = i2s_read_reg(dev->i2s_base, dev->i2s_reg_comp1);
u32 comp2 = i2s_read_reg(dev->i2s_base, dev->i2s_reg_comp2);
+ u32 fifo_depth = 1 << (1 + COMP1_FIFO_DEPTH_GLOBAL(comp1));
u32 idx;

if (dev->capability & DWC_I2S_RECORD &&
@@ -536,6 +865,7 @@ static int dw_configure_dai(struct dw_i2s_dev *dev,
dev->capability |= DW_I2S_SLAVE;
}

+ dev->fifo_th = fifo_depth / 2;
return 0;
}

@@ -620,7 +950,7 @@ static int dw_i2s_probe(struct platform_device *pdev)
const struct i2s_platform_data *pdata = pdev->dev.platform_data;
struct dw_i2s_dev *dev;
struct resource *res;
- int ret;
+ int ret, irq_number;
struct snd_soc_dai_driver *dw_i2s_dai;
const char *clk_id;

@@ -643,6 +973,19 @@ static int dw_i2s_probe(struct platform_device *pdev)
if (IS_ERR(dev->i2s_base))
return PTR_ERR(dev->i2s_base);

+ irq_number = platform_get_irq(pdev, 0);
+ if (irq_number <= 0) {
+ dev_err(&pdev->dev, "get irq fail\n");
+ return -EINVAL;
+ }
+
+ ret = devm_request_irq(&pdev->dev, irq_number, i2s_irq_handler,
+ IRQF_SHARED, "dw_i2s_irq_handler", dev);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "request irq fail\n");
+ return ret;
+ }
+
dev->dev = &pdev->dev;

dev->i2s_reg_comp1 = I2S_COMP_PARAM_1;
@@ -671,14 +1014,22 @@ static int dw_i2s_probe(struct platform_device *pdev)
return -ENODEV;
}
}
- dev->clk = devm_clk_get(&pdev->dev, clk_id);

- if (IS_ERR(dev->clk))
- return PTR_ERR(dev->clk);
+ if (dev->i2s_clk_cfg ||
+ of_get_property(pdev->dev.of_node, "clocks", NULL)) {
+ dev->clk = devm_clk_get(&pdev->dev, clk_id);
+
+ if (IS_ERR(dev->clk))
+ return PTR_ERR(dev->clk);

- ret = clk_prepare_enable(dev->clk);
- if (ret < 0)
- return ret;
+ ret = clk_prepare_enable(dev->clk);
+ if (ret < 0)
+ return ret;
+ } else {
+ /* Use internal PLL config */
+ dev->i2s_clk_cfg = i2s_pll_cfg;
+ dev->clk = NULL;
+ }
}

dev_set_drvdata(&pdev->dev, dev);
@@ -690,7 +1041,14 @@ static int dw_i2s_probe(struct platform_device *pdev)
}

if (!pdata) {
- ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
+ if (of_get_property(pdev->dev.of_node, "dmas", NULL)) {
+ /* Using DMA */
+ ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
+ } else {
+ ret = snd_soc_register_platform(&pdev->dev,
+ &dw_pcm_soc_platform);
+ }
+
if (ret) {
dev_err(&pdev->dev,
"Could not register PCM: %d\n", ret);
@@ -714,6 +1072,7 @@ static int dw_i2s_remove(struct platform_device *pdev)
clk_disable_unprepare(dev->clk);

pm_runtime_disable(&pdev->dev);
+ snd_soc_unregister_platform(&pdev->dev);
return 0;
}

--
1.9.1