ASoC: fsl: add imx-pcm-dma v2 platform driver (part 1)

which don't request the dma channel in the probe, but request
dma channel when needed. for the dma channel of cpu dai in BE
can be reused by the FE.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
[ Aisheng: spli SAI DAI changes ]
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>

1 files changed, 230 insertions, 0 deletions

diff --git a/sound/soc/fsl/imx-pcm-dma-v2.c b/sound/soc/fsl/imx-pcm-dma-v2.c
new file mode 100644
index 000000000000..38ff1375ff3d
--- /dev/null
+++ b/sound/soc/fsl/imx-pcm-dma-v2.c
@@ -0,0 +1,230 @@
+/*
+ * imx-pcm-dma-v2.c -- ALSA Soc Audio Layer
+ *
+ * Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de>
+ *
+ * This code is based on code copyrighted by Freescale,
+ * Liam Girdwood, Javier Martin and probably others.
+ *
+ *  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.
+ */
+#include <linux/dma-mapping.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/dmaengine_pcm.h>
+#include <sound/soc.h>
+
+#include "imx-pcm.h"
+
+static const struct snd_pcm_hardware imx_pcm_hardware = {
+	.info = SNDRV_PCM_INFO_INTERLEAVED |
+		SNDRV_PCM_INFO_BLOCK_TRANSFER |
+		SNDRV_PCM_INFO_MMAP |
+		SNDRV_PCM_INFO_MMAP_VALID |
+		SNDRV_PCM_INFO_PAUSE |
+		SNDRV_PCM_INFO_RESUME,
+	.buffer_bytes_max = IMX_SSI_DMABUF_SIZE,
+	.period_bytes_min = 128,
+	.period_bytes_max = 65532, /* Limited by SDMA engine */
+	.periods_min = 2,
+	.periods_max = 255,
+	.fifo_size = 0,
+};
+
+static bool imx_dma_filter_fn(struct dma_chan *chan, void *param)
+{
+	if (!imx_dma_is_general_purpose(chan))
+		return false;
+
+	chan->private = param;
+
+	return true;
+}
+
+/* this may get called several times by oss emulation */
+static int imx_pcm_hw_params(struct snd_pcm_substream *substream,
+			      struct snd_pcm_hw_params *params)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct imx_pcm_dma_data *dma_data;
+	struct dma_slave_config config;
+	struct dma_chan *chan;
+	int err = 0;
+
+	dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
+
+	/* return if this is a bufferless transfer e.g.
+	 * codec <--> BT codec or GSM modem -- lg FIXME
+	 */
+	if (!dma_data)
+		return 0;
+
+	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
+	runtime->dma_bytes = params_buffer_bytes(params);
+
+	chan = snd_dmaengine_pcm_get_chan(substream);
+	if (!chan)
+		return -EINVAL;
+
+	/* fills in addr_width and direction */
+	err = snd_hwparams_to_dma_slave_config(substream, params, &config);
+	if (err)
+		return err;
+
+	snd_dmaengine_pcm_set_config_from_dai_data(substream,
+			snd_soc_dai_get_dma_data(rtd->cpu_dai, substream),
+			&config);
+
+	return dmaengine_slave_config(chan, &config);
+}
+
+static int imx_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+	snd_pcm_set_runtime_buffer(substream, NULL);
+	return 0;
+}
+
+static snd_pcm_uframes_t imx_pcm_pointer(struct snd_pcm_substream *substream)
+{
+	return snd_dmaengine_pcm_pointer(substream);
+}
+
+static int imx_pcm_open(struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct snd_dmaengine_dai_dma_data *dma_data;
+	int ret;
+
+	snd_soc_set_runtime_hwparams(substream, &imx_pcm_hardware);
+
+	dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
+
+	/* DT boot: filter_data is the DMA name */
+	if (rtd->cpu_dai->dev->of_node) {
+		struct dma_chan *chan;
+
+		chan = dma_request_slave_channel(rtd->cpu_dai->dev,
+						 dma_data->filter_data);
+		ret = snd_dmaengine_pcm_open(substream, chan);
+	} else {
+		ret = snd_dmaengine_pcm_open_request_chan(substream,
+							  imx_dma_filter_fn,
+							  dma_data->filter_data);
+	}
+	return ret;
+}
+
+static int imx_pcm_mmap(struct snd_pcm_substream *substream,
+	struct vm_area_struct *vma)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+
+	return dma_mmap_writecombine(substream->pcm->card->dev, vma,
+				     runtime->dma_area,
+				     runtime->dma_addr,
+				     runtime->dma_bytes);
+}
+
+static struct snd_pcm_ops imx_pcm_ops = {
+	.open		= imx_pcm_open,
+	.close		= snd_dmaengine_pcm_close_release_chan,
+	.ioctl		= snd_pcm_lib_ioctl,
+	.hw_params	= imx_pcm_hw_params,
+	.hw_free	= imx_pcm_hw_free,
+	.trigger	= snd_dmaengine_pcm_trigger,
+	.pointer	= imx_pcm_pointer,
+	.mmap		= imx_pcm_mmap,
+};
+
+static int imx_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 = imx_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_writecombine(pcm->card->dev, size,
+					   &buf->addr, GFP_KERNEL);
+	if (!buf->area)
+		return -ENOMEM;
+
+	buf->bytes = size;
+	return 0;
+}
+
+static void imx_pcm_free_dma_buffers(struct snd_pcm *pcm)
+{
+	struct snd_pcm_substream *substream;
+	struct snd_dma_buffer *buf;
+	int stream;
+
+	for (stream = SNDRV_PCM_STREAM_PLAYBACK; stream < SNDRV_PCM_STREAM_LAST; stream++) {
+		substream = pcm->streams[stream].substream;
+		if (!substream)
+			continue;
+
+		buf = &substream->dma_buffer;
+		if (!buf->area)
+			continue;
+
+		dma_free_writecombine(pcm->card->dev, buf->bytes,
+				      buf->area, buf->addr);
+		buf->area = NULL;
+	}
+}
+
+static int imx_pcm_new(struct snd_soc_pcm_runtime *rtd)
+{
+	struct snd_card *card = rtd->card->snd_card;
+	struct snd_pcm *pcm = rtd->pcm;
+	int ret;
+
+	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
+	if (ret)
+		return ret;
+
+	if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
+		ret = imx_pcm_preallocate_dma_buffer(pcm,
+			SNDRV_PCM_STREAM_PLAYBACK);
+		if (ret)
+			goto out;
+	}
+
+	if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
+		ret = imx_pcm_preallocate_dma_buffer(pcm,
+			SNDRV_PCM_STREAM_CAPTURE);
+		if (ret)
+			goto out;
+	}
+
+out:
+	/* free preallocated buffers in case of error */
+	if (ret)
+		imx_pcm_free_dma_buffers(pcm);
+
+	return ret;
+}
+
+static struct snd_soc_component_driver imx_soc_platform = {
+	.ops		= &imx_pcm_ops,
+	.pcm_new	= imx_pcm_new,
+	.pcm_free	= imx_pcm_free_dma_buffers,
+};
+
+int imx_pcm_platform_register(struct device *dev)
+{
+	return devm_snd_soc_register_component(dev, &imx_soc_platform, NULL, 0);
+}
+EXPORT_SYMBOL_GPL(imx_pcm_platform_register);
+
+MODULE_LICENSE("GPL");