1 files changed, 281 insertions, 0 deletions

diff --git a/sound/soc/dwc/dwc-pcm.c b/sound/soc/dwc/dwc-pcm.c
new file mode 100644
index 000000000000..406fd867117b
--- /dev/null
+++ b/sound/soc/dwc/dwc-pcm.c
@@ -0,0 +1,281 @@
+/*
+ * ALSA SoC Synopsys PIO PCM for I2S driver
+ *
+ * sound/soc/dwc/designware_pcm.c
+ *
+ * Copyright (C) 2016 Synopsys
+ * Jose Abreu <joabreu@synopsys.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/io.h>
+#include <linux/rcupdate.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include "local.h"
+
+#define BUFFER_BYTES_MAX	(3 * 2 * 8 * PERIOD_BYTES_MIN)
+#define PERIOD_BYTES_MIN	4096
+#define PERIODS_MIN		2
+
+#define dw_pcm_tx_fn(sample_bits) \
+static unsigned int dw_pcm_tx_##sample_bits(struct dw_i2s_dev *dev, \
+		struct snd_pcm_runtime *runtime, unsigned int tx_ptr, \
+		bool *period_elapsed) \
+{ \
+	const u##sample_bits (*p)[2] = (void *)runtime->dma_area; \
+	unsigned int period_pos = tx_ptr % runtime->period_size; \
+	int i; \
+\
+	for (i = 0; i < dev->fifo_th; i++) { \
+		iowrite32(p[tx_ptr][0], dev->i2s_base + LRBR_LTHR(0)); \
+		iowrite32(p[tx_ptr][1], dev->i2s_base + RRBR_RTHR(0)); \
+		period_pos++; \
+		if (++tx_ptr >= runtime->buffer_size) \
+			tx_ptr = 0; \
+	} \
+	*period_elapsed = period_pos >= runtime->period_size; \
+	return tx_ptr; \
+}
+
+#define dw_pcm_rx_fn(sample_bits) \
+static unsigned int dw_pcm_rx_##sample_bits(struct dw_i2s_dev *dev, \
+		struct snd_pcm_runtime *runtime, unsigned int rx_ptr, \
+		bool *period_elapsed) \
+{ \
+	u##sample_bits (*p)[2] = (void *)runtime->dma_area; \
+	unsigned int period_pos = rx_ptr % runtime->period_size; \
+	int i; \
+\
+	for (i = 0; i < dev->fifo_th; i++) { \
+		p[rx_ptr][0] = ioread32(dev->i2s_base + LRBR_LTHR(0)); \
+		p[rx_ptr][1] = ioread32(dev->i2s_base + RRBR_RTHR(0)); \
+		period_pos++; \
+		if (++rx_ptr >= runtime->buffer_size) \
+			rx_ptr = 0; \
+	} \
+	*period_elapsed = period_pos >= runtime->period_size; \
+	return rx_ptr; \
+}
+
+dw_pcm_tx_fn(16);
+dw_pcm_tx_fn(32);
+dw_pcm_rx_fn(16);
+dw_pcm_rx_fn(32);
+
+#undef dw_pcm_tx_fn
+#undef dw_pcm_rx_fn
+
+static const struct snd_pcm_hardware dw_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_32000 |
+		SNDRV_PCM_RATE_44100 |
+		SNDRV_PCM_RATE_48000,
+	.rate_min = 32000,
+	.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 dw_pcm_transfer(struct dw_i2s_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);
+			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);
+			cmpxchg(&dev->rx_ptr, ptr, new_ptr);
+		}
+
+		if (period_elapsed)
+			snd_pcm_period_elapsed(substream);
+	}
+	rcu_read_unlock();
+}
+
+void dw_pcm_push_tx(struct dw_i2s_dev *dev)
+{
+	dw_pcm_transfer(dev, true);
+}
+
+void dw_pcm_pop_rx(struct dw_i2s_dev *dev)
+{
+	dw_pcm_transfer(dev, false);
+}
+
+static int dw_pcm_open(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct dw_i2s_dev *dev = snd_soc_dai_get_drvdata(rtd->cpu_dai);
+
+	snd_soc_set_runtime_hwparams(substream, &dw_pcm_hardware);
+	snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
+	runtime->private_data = dev;
+
+	return 0;
+}
+
+static int dw_pcm_close(struct snd_pcm_substream *substream)
+{
+	synchronize_rcu();
+	return 0;
+}
+
+static int dw_pcm_hw_params(struct snd_pcm_substream *substream,
+		struct snd_pcm_hw_params *hw_params)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct dw_i2s_dev *dev = runtime->private_data;
+	int ret;
+
+	switch (params_channels(hw_params)) {
+	case 2:
+		break;
+	default:
+		dev_err(dev->dev, "invalid channels number\n");
+		return -EINVAL;
+	}
+
+	switch (params_format(hw_params)) {
+	case SNDRV_PCM_FORMAT_S16_LE:
+		dev->tx_fn = dw_pcm_tx_16;
+		dev->rx_fn = dw_pcm_rx_16;
+		break;
+	case SNDRV_PCM_FORMAT_S24_LE:
+	case SNDRV_PCM_FORMAT_S32_LE:
+		dev->tx_fn = dw_pcm_tx_32;
+		dev->rx_fn = dw_pcm_rx_32;
+		break;
+	default:
+		dev_err(dev->dev, "invalid format\n");
+		return -EINVAL;
+	}
+
+	ret = snd_pcm_lib_malloc_pages(substream,
+			params_buffer_bytes(hw_params));
+	if (ret < 0)
+		return ret;
+	else
+		return 0;
+}
+
+static int dw_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+	return snd_pcm_lib_free_pages(substream);
+}
+
+static int dw_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct dw_i2s_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 dw_pcm_pointer(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct dw_i2s_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 dw_pcm_new(struct snd_soc_pcm_runtime *rtd)
+{
+	size_t size = dw_pcm_hardware.buffer_bytes_max;
+
+	return snd_pcm_lib_preallocate_pages_for_all(rtd->pcm,
+			SNDRV_DMA_TYPE_CONTINUOUS,
+			snd_dma_continuous_data(GFP_KERNEL), size, size);
+}
+
+static void dw_pcm_free(struct snd_pcm *pcm)
+{
+	snd_pcm_lib_preallocate_free_for_all(pcm);
+}
+
+static const 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,
+	.trigger = dw_pcm_trigger,
+	.pointer = dw_pcm_pointer,
+};
+
+static const struct snd_soc_platform_driver dw_pcm_platform = {
+	.pcm_new = dw_pcm_new,
+	.pcm_free = dw_pcm_free,
+	.ops = &dw_pcm_ops,
+};
+
+int dw_pcm_register(struct platform_device *pdev)
+{
+	return devm_snd_soc_register_platform(&pdev->dev, &dw_pcm_platform);
+}