1 files changed, 288 insertions, 0 deletions
diff --git a/sound/soc/starfive/spdif-pcm.c b/sound/soc/starfive/spdif-pcm.c
new file mode 100644
index 000000000000..1763adc19776
--- /dev/null
+++ b/sound/soc/starfive/spdif-pcm.c
@@ -0,0 +1,288 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2021 StarFive Technology Co., Ltd.
+ */
+#include <linux/io.h>
+#include <linux/rcupdate.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+
+#include "spdif.h"
+
+#define BUFFER_BYTES_MAX	(3 * 2 * 8 * PERIOD_BYTES_MIN)
+#define PERIOD_BYTES_MIN	4096
+#define PERIODS_MIN			2
+
+static unsigned int sf_spdif_pcm_tx(struct sf_spdif_dev *dev,
+		struct snd_pcm_runtime *runtime, unsigned int tx_ptr,
+		bool *period_elapsed, snd_pcm_format_t format)
+{
+	const u16 (*p16)[2] = (void *)runtime->dma_area;
+	const u32 (*p32)[2] = (void *)runtime->dma_area;
+	u32 data[2];
+	unsigned int period_pos = tx_ptr % runtime->period_size;
+	int i;
+
+	for (i = 0; i < dev->fifo_th; i++) {
+		if (SNDRV_PCM_FORMAT_S16_LE == format) {
+			data[0] = p16[tx_ptr][0];
+			data[1] = p16[tx_ptr][1];
+			data[0] = data[0]<<8;
+			data[1] = data[1]<<8;
+		} else if (SNDRV_PCM_FORMAT_S24_LE == format) {
+			data[0] = p32[tx_ptr][0];
+			data[1] = p32[tx_ptr][1];
+		} else if (SNDRV_PCM_FORMAT_S32_LE == format) {
+			data[0] = p32[tx_ptr][0];
+			data[1] = p32[tx_ptr][1];
+			data[0] = data[0]>>8;
+			data[1] = data[1]>>8;
+		}
+
+		iowrite32(data[0], dev->spdif_base + SPDIF_FIFO_ADDR);
+		iowrite32(data[1], dev->spdif_base + SPDIF_FIFO_ADDR);
+		period_pos++;
+		if (++tx_ptr >= runtime->buffer_size) {
+			tx_ptr = 0;
+		}
+	}
+
+	*period_elapsed = period_pos >= runtime->period_size;
+	return tx_ptr;
+}
+
+static unsigned int sf_spdif_pcm_rx(struct sf_spdif_dev *dev,
+		struct snd_pcm_runtime *runtime, unsigned int rx_ptr,
+		bool *period_elapsed, snd_pcm_format_t format)
+{
+	u16 (*p16)[2] = (void *)runtime->dma_area;
+	u32 (*p32)[2] = (void *)runtime->dma_area;
+	u32 data[2];
+	unsigned int period_pos = rx_ptr % runtime->period_size;
+	int i;
+
+	for (i = 0; i < dev->fifo_th; i++) {
+		data[0] = ioread32(dev->spdif_base + SPDIF_FIFO_ADDR);
+		data[1] = ioread32(dev->spdif_base + SPDIF_FIFO_ADDR);
+		if (SNDRV_PCM_FORMAT_S16_LE == format) {
+			p16[rx_ptr][0] = data[0]>>8;
+			p16[rx_ptr][1] = data[1]>>8;
+		} else if (SNDRV_PCM_FORMAT_S24_LE == format) {
+			p32[rx_ptr][0] = data[0];
+			p32[rx_ptr][1] = data[1];
+		} else if (SNDRV_PCM_FORMAT_S32_LE == format) {
+			p32[rx_ptr][0] = data[0]<<8;
+			p32[rx_ptr][1] = data[1]<<8;
+		}
+
+		period_pos++;
+		if (++rx_ptr >= runtime->buffer_size)
+			rx_ptr = 0;
+	}
+
+	*period_elapsed = period_pos >= runtime->period_size;
+	return rx_ptr;
+}
+
+static const struct snd_pcm_hardware sf_pcm_hardware = {
+	.info = SNDRV_PCM_INFO_INTERLEAVED |
+		SNDRV_PCM_INFO_MMAP |
+		SNDRV_PCM_INFO_MMAP_VALID |
+		SNDRV_PCM_INFO_BLOCK_TRANSFER,
+	.rates = SNDRV_PCM_RATE_8000 |
+		SNDRV_PCM_RATE_11025 |
+		SNDRV_PCM_RATE_16000 |
+		SNDRV_PCM_RATE_22050 |
+		SNDRV_PCM_RATE_32000 |
+		SNDRV_PCM_RATE_44100 |
+		SNDRV_PCM_RATE_48000,
+	.rate_min = 8000,
+	.rate_max = 48000,
+	.formats = SNDRV_PCM_FMTBIT_S16_LE |
+		SNDRV_PCM_FMTBIT_S24_LE |
+		SNDRV_PCM_FMTBIT_S32_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,
+	.fifo_size = 16,
+};
+
+static void sf_spdif_pcm_transfer(struct sf_spdif_dev *dev, bool push)
+{
+	struct snd_pcm_substream *substream;
+	bool active, period_elapsed;
+
+	rcu_read_lock();
+	if (push)
+		substream = rcu_dereference(dev->tx_substream);
+	else
+		substream = rcu_dereference(dev->rx_substream);
+	active = substream && snd_pcm_running(substream);
+	if (active) {
+		unsigned int ptr;
+		unsigned int new_ptr;
+
+		if (push) {
+			ptr = READ_ONCE(dev->tx_ptr);
+			new_ptr = dev->tx_fn(dev, substream->runtime, ptr,
+					&period_elapsed, dev->format);
+			cmpxchg(&dev->tx_ptr, ptr, new_ptr);
+		} else {
+			ptr = READ_ONCE(dev->rx_ptr);
+			new_ptr = dev->rx_fn(dev, substream->runtime, ptr,
+					&period_elapsed, dev->format);
+			cmpxchg(&dev->rx_ptr, ptr, new_ptr);
+		}
+
+		if (period_elapsed)
+			snd_pcm_period_elapsed(substream);
+	}
+	rcu_read_unlock();
+}
+
+void sf_spdif_pcm_push_tx(struct sf_spdif_dev *dev)
+{
+	sf_spdif_pcm_transfer(dev, true);
+}
+
+void sf_spdif_pcm_pop_rx(struct sf_spdif_dev *dev)
+{
+	sf_spdif_pcm_transfer(dev, false);
+}
+
+static int sf_pcm_open(struct snd_soc_component *component,
+			struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
+	struct sf_spdif_dev *dev = snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0));
+
+	snd_soc_set_runtime_hwparams(substream, &sf_pcm_hardware);
+	snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
+	runtime->private_data = dev;
+
+	return 0;
+}
+
+static int sf_pcm_close(struct snd_soc_component *component,
+			struct snd_pcm_substream *substream)
+{
+	synchronize_rcu();
+	return 0;
+}
+
+static int sf_pcm_hw_params(struct snd_soc_component *component,
+			struct snd_pcm_substream *substream,
+			struct snd_pcm_hw_params *hw_params)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct sf_spdif_dev *dev = runtime->private_data;
+
+	switch (params_channels(hw_params)) {
+	case 2:
+		break;
+	default:
+		dev_err(dev->dev, "invalid channels number\n");
+		return -EINVAL;
+	}
+
+	dev->format = params_format(hw_params);
+	switch (dev->format) {
+	case SNDRV_PCM_FORMAT_S16_LE:
+	case SNDRV_PCM_FORMAT_S24_LE:
+	case SNDRV_PCM_FORMAT_S32_LE:
+		break;
+	default:
+		dev_err(dev->dev, "invalid format\n");
+		return -EINVAL;
+	}
+
+	dev->tx_fn = sf_spdif_pcm_tx;
+	dev->rx_fn = sf_spdif_pcm_rx;
+
+	return 0;
+}
+
+static int sf_pcm_trigger(struct snd_soc_component *component,
+			struct snd_pcm_substream *substream, int cmd)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct sf_spdif_dev *dev = runtime->private_data;
+	int ret = 0;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+			WRITE_ONCE(dev->tx_ptr, 0);
+			rcu_assign_pointer(dev->tx_substream, substream);
+		} else {
+			WRITE_ONCE(dev->rx_ptr, 0);
+			rcu_assign_pointer(dev->rx_substream, substream);
+		}
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+			rcu_assign_pointer(dev->tx_substream, NULL);
+		else
+			rcu_assign_pointer(dev->rx_substream, NULL);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+static snd_pcm_uframes_t sf_pcm_pointer(struct snd_soc_component *component,
+					struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct sf_spdif_dev *dev = runtime->private_data;
+	snd_pcm_uframes_t pos;
+
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+		pos = READ_ONCE(dev->tx_ptr);
+	}
+	else {
+		pos = READ_ONCE(dev->rx_ptr);
+	}
+
+	return pos < runtime->buffer_size ? pos : 0;
+}
+
+static int sf_pcm_new(struct snd_soc_component *component,
+			struct snd_soc_pcm_runtime *rtd)
+{
+	size_t size = sf_pcm_hardware.buffer_bytes_max;
+
+	snd_pcm_set_managed_buffer_all(rtd->pcm,
+			SNDRV_DMA_TYPE_CONTINUOUS,
+			NULL, size, size);
+
+	return 0;
+}
+
+static const struct snd_soc_component_driver sf_pcm_component = {
+	.open		= sf_pcm_open,
+	.close		= sf_pcm_close,
+	.hw_params	= sf_pcm_hw_params,
+	.trigger	= sf_pcm_trigger,
+	.pointer	= sf_pcm_pointer,
+	.pcm_construct	= sf_pcm_new,
+};
+
+int sf_spdif_pcm_register(struct platform_device *pdev)
+{
+	return devm_snd_soc_register_component(&pdev->dev, &sf_pcm_component,
+					NULL, 0);
+}
+