ASoC: blackfin I2S(TDM mode) CPU DAI driver

The I2S DAI driver for blackfin SPORT, but works in TDM mode.
I2S is not a special case of TDM with only left and right two slots for
SPORT interface. I2S coordinates with TDM in SPORT, but not a part of
TDM. TDM require different hardware configuration with I2S, not only
different slot number.  One is "Stereo Serial Operation" mode of SPORT,
the other one is "Multichannel Operation" mode. They are incompatible
at the same time.
Hardware and DMA description and data transfer flow are much different
for I2S and TDM. Merging them as a whole will be very ugly and difficult
to maintain.
So we don't define a new DAI type, but give two DAI instances for standard
I2S and TDM, both in I2S-family DAI type. The TDM instance still uses the
I2S-family DAI type.

Signed-off-by: Barry Song <21cnbao@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 330 insertions, 0 deletions

diff --git a/sound/soc/blackfin/bf5xx-tdm-pcm.c b/sound/soc/blackfin/bf5xx-tdm-pcm.c
new file mode 100644
index 00000000000..af7fa8d7ff0
--- /dev/null
+++ b/sound/soc/blackfin/bf5xx-tdm-pcm.c
@@ -0,0 +1,330 @@
+/*
+ * File:         sound/soc/blackfin/bf5xx-tdm-pcm.c
+ * Author:       Barry Song <Barry.Song@analog.com>
+ *
+ * Created:      Tue June 06 2009
+ * Description:  DMA driver for tdm codec
+ *
+ * Modified:
+ *               Copyright 2009 Analog Devices Inc.
+ *
+ * Bugs:         Enter bugs at http://blackfin.uclinux.org/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see the file COPYING, or write
+ * to the Free Software Foundation, Inc.,
+ * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/dma-mapping.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+
+#include <asm/dma.h>
+
+#include "bf5xx-tdm-pcm.h"
+#include "bf5xx-tdm.h"
+#include "bf5xx-sport.h"
+
+#define PCM_BUFFER_MAX  0x10000
+#define FRAGMENT_SIZE_MIN  (4*1024)
+#define FRAGMENTS_MIN  2
+#define FRAGMENTS_MAX  32
+
+static void bf5xx_dma_irq(void *data)
+{
+	struct snd_pcm_substream *pcm = data;
+	snd_pcm_period_elapsed(pcm);
+}
+
+static const struct snd_pcm_hardware bf5xx_pcm_hardware = {
+	.info = (SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
+		SNDRV_PCM_INFO_RESUME),
+	.formats =          SNDRV_PCM_FMTBIT_S32_LE,
+	.rates =            SNDRV_PCM_RATE_48000,
+	.channels_min =     2,
+	.channels_max =     8,
+	.buffer_bytes_max = PCM_BUFFER_MAX,
+	.period_bytes_min = FRAGMENT_SIZE_MIN,
+	.period_bytes_max = PCM_BUFFER_MAX/2,
+	.periods_min =      FRAGMENTS_MIN,
+	.periods_max =      FRAGMENTS_MAX,
+};
+
+static int bf5xx_pcm_hw_params(struct snd_pcm_substream *substream,
+	struct snd_pcm_hw_params *params)
+{
+	size_t size = bf5xx_pcm_hardware.buffer_bytes_max;
+	snd_pcm_lib_malloc_pages(substream, size * 4);
+
+	return 0;
+}
+
+static int bf5xx_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+	snd_pcm_lib_free_pages(substream);
+
+	return 0;
+}
+
+static int bf5xx_pcm_prepare(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct sport_device *sport = runtime->private_data;
+	int fragsize_bytes = frames_to_bytes(runtime, runtime->period_size);
+
+	fragsize_bytes /= runtime->channels;
+	/* inflate the fragsize to match the dma width of SPORT */
+	fragsize_bytes *= 8;
+
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+		sport_set_tx_callback(sport, bf5xx_dma_irq, substream);
+		sport_config_tx_dma(sport, runtime->dma_area,
+			runtime->periods, fragsize_bytes);
+	} else {
+		sport_set_rx_callback(sport, bf5xx_dma_irq, substream);
+		sport_config_rx_dma(sport, runtime->dma_area,
+			runtime->periods, fragsize_bytes);
+	}
+
+	return 0;
+}
+
+static int bf5xx_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct sport_device *sport = runtime->private_data;
+	int ret = 0;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+			sport_tx_start(sport);
+		else
+			sport_rx_start(sport);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+			sport_tx_stop(sport);
+		else
+			sport_rx_stop(sport);
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static snd_pcm_uframes_t bf5xx_pcm_pointer(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct sport_device *sport = runtime->private_data;
+	unsigned int diff;
+	snd_pcm_uframes_t frames;
+
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+		diff = sport_curr_offset_tx(sport);
+		frames = diff / (8*4); /* 32 bytes per frame */
+	} else {
+		diff = sport_curr_offset_rx(sport);
+		frames = diff / (8*4);
+	}
+	return frames;
+}
+
+static int bf5xx_pcm_open(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	int ret = 0;
+
+	snd_soc_set_runtime_hwparams(substream, &bf5xx_pcm_hardware);
+
+	ret = snd_pcm_hw_constraint_integer(runtime,
+		SNDRV_PCM_HW_PARAM_PERIODS);
+	if (ret < 0)
+		goto out;
+
+	if (sport_handle != NULL)
+		runtime->private_data = sport_handle;
+	else {
+		pr_err("sport_handle is NULL\n");
+		ret = -ENODEV;
+	}
+out:
+	return ret;
+}
+
+static int bf5xx_pcm_copy(struct snd_pcm_substream *substream, int channel,
+	snd_pcm_uframes_t pos, void *buf, snd_pcm_uframes_t count)
+{
+	unsigned int *src;
+	unsigned int *dst;
+	int i;
+
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+		src = buf;
+		dst = (unsigned int *)substream->runtime->dma_area;
+
+		dst += pos * 8;
+		while (count--) {
+			for (i = 0; i < substream->runtime->channels; i++)
+				*(dst + i) = *src++;
+			dst += 8;
+		}
+	} else {
+		src = (unsigned int *)substream->runtime->dma_area;
+		dst = buf;
+
+		src += pos * 8;
+		while (count--) {
+			for (i = 0; i < substream->runtime->channels; i++)
+				*dst++ = *(src+i);
+			src += 8;
+		}
+	}
+
+	return 0;
+}
+
+static int bf5xx_pcm_silence(struct snd_pcm_substream *substream,
+	int channel, snd_pcm_uframes_t pos, snd_pcm_uframes_t count)
+{
+	unsigned char *buf = substream->runtime->dma_area;
+	buf += pos * 8 * 4;
+	memset(buf, '\0', count * 8 * 4);
+
+	return 0;
+}
+
+
+struct snd_pcm_ops bf5xx_pcm_tdm_ops = {
+	.open           = bf5xx_pcm_open,
+	.ioctl          = snd_pcm_lib_ioctl,
+	.hw_params      = bf5xx_pcm_hw_params,
+	.hw_free        = bf5xx_pcm_hw_free,
+	.prepare        = bf5xx_pcm_prepare,
+	.trigger        = bf5xx_pcm_trigger,
+	.pointer        = bf5xx_pcm_pointer,
+	.copy           = bf5xx_pcm_copy,
+	.silence        = bf5xx_pcm_silence,
+};
+
+static int bf5xx_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
+{
+	struct snd_pcm_substream *substream = pcm->streams[stream].substream;
+	struct snd_dma_buffer *buf = &substream->dma_buffer;
+	size_t size = bf5xx_pcm_hardware.buffer_bytes_max;
+
+	buf->dev.type = SNDRV_DMA_TYPE_DEV;
+	buf->dev.dev = pcm->card->dev;
+	buf->private_data = NULL;
+	buf->area = dma_alloc_coherent(pcm->card->dev, size * 4,
+		&buf->addr, GFP_KERNEL);
+	if (!buf->area) {
+		pr_err("Failed to allocate dma memory \
+			Please increase uncached DMA memory region\n");
+		return -ENOMEM;
+	}
+	buf->bytes = size;
+
+	if (stream == SNDRV_PCM_STREAM_PLAYBACK)
+		sport_handle->tx_buf = buf->area;
+	else
+		sport_handle->rx_buf = buf->area;
+
+	return 0;
+}
+
+static void bf5xx_pcm_free_dma_buffers(struct snd_pcm *pcm)
+{
+	struct snd_pcm_substream *substream;
+	struct snd_dma_buffer *buf;
+	int stream;
+
+	for (stream = 0; stream < 2; stream++) {
+		substream = pcm->streams[stream].substream;
+		if (!substream)
+			continue;
+
+		buf = &substream->dma_buffer;
+		if (!buf->area)
+			continue;
+		dma_free_coherent(NULL, buf->bytes, buf->area, 0);
+		buf->area = NULL;
+	}
+	if (sport_handle)
+		sport_done(sport_handle);
+}
+
+static u64 bf5xx_pcm_dmamask = DMA_32BIT_MASK;
+
+static int bf5xx_pcm_tdm_new(struct snd_card *card, struct snd_soc_dai *dai,
+	struct snd_pcm *pcm)
+{
+	int ret = 0;
+
+	if (!card->dev->dma_mask)
+		card->dev->dma_mask = &bf5xx_pcm_dmamask;
+	if (!card->dev->coherent_dma_mask)
+		card->dev->coherent_dma_mask = DMA_32BIT_MASK;
+
+	if (dai->playback.channels_min) {
+		ret = bf5xx_pcm_preallocate_dma_buffer(pcm,
+			SNDRV_PCM_STREAM_PLAYBACK);
+		if (ret)
+			goto out;
+	}
+
+	if (dai->capture.channels_min) {
+		ret = bf5xx_pcm_preallocate_dma_buffer(pcm,
+			SNDRV_PCM_STREAM_CAPTURE);
+		if (ret)
+			goto out;
+	}
+out:
+	return ret;
+}
+
+struct snd_soc_platform bf5xx_tdm_soc_platform = {
+	.name           = "bf5xx-audio",
+	.pcm_ops        = &bf5xx_pcm_tdm_ops,
+	.pcm_new        = bf5xx_pcm_tdm_new,
+	.pcm_free       = bf5xx_pcm_free_dma_buffers,
+};
+EXPORT_SYMBOL_GPL(bf5xx_tdm_soc_platform);
+
+static int __init bfin_pcm_tdm_init(void)
+{
+	return snd_soc_register_platform(&bf5xx_tdm_soc_platform);
+}
+module_init(bfin_pcm_tdm_init);
+
+static void __exit bfin_pcm_tdm_exit(void)
+{
+	snd_soc_unregister_platform(&bf5xx_tdm_soc_platform);
+}
+module_exit(bfin_pcm_tdm_exit);
+
+MODULE_AUTHOR("Barry Song");
+MODULE_DESCRIPTION("ADI Blackfin TDM PCM DMA module");
+MODULE_LICENSE("GPL");