1 files changed, 337 insertions, 0 deletions
diff --git a/sound/soc/au1x/dma.c b/sound/soc/au1x/dma.c
new file mode 100644
index 000000000..24cc7f40d
--- /dev/null
+++ b/sound/soc/au1x/dma.c
@@ -0,0 +1,337 @@
+/*
+ * Au1000/Au1500/Au1100 Audio DMA support.
+ *
+ * (c) 2011 Manuel Lauss <manuel.lauss@googlemail.com>
+ *
+ * copied almost verbatim from the old ALSA driver, written by
+ *			Charles Eidsness <charles@cooper-street.com>
+ */
+
+#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/mach-au1x00/au1000.h>
+#include <asm/mach-au1x00/au1000_dma.h>
+
+#include "psc.h"
+
+struct pcm_period {
+	u32 start;
+	u32 relative_end;	/* relative to start of buffer */
+	struct pcm_period *next;
+};
+
+struct audio_stream {
+	struct snd_pcm_substream *substream;
+	int dma;
+	struct pcm_period *buffer;
+	unsigned int period_size;
+	unsigned int periods;
+};
+
+struct alchemy_pcm_ctx {
+	struct audio_stream stream[2];	/* playback & capture */
+};
+
+static void au1000_release_dma_link(struct audio_stream *stream)
+{
+	struct pcm_period *pointer;
+	struct pcm_period *pointer_next;
+
+	stream->period_size = 0;
+	stream->periods = 0;
+	pointer = stream->buffer;
+	if (!pointer)
+		return;
+	do {
+		pointer_next = pointer->next;
+		kfree(pointer);
+		pointer = pointer_next;
+	} while (pointer != stream->buffer);
+	stream->buffer = NULL;
+}
+
+static int au1000_setup_dma_link(struct audio_stream *stream,
+				 unsigned int period_bytes,
+				 unsigned int periods)
+{
+	struct snd_pcm_substream *substream = stream->substream;
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct pcm_period *pointer;
+	unsigned long dma_start;
+	int i;
+
+	dma_start = virt_to_phys(runtime->dma_area);
+
+	if (stream->period_size == period_bytes &&
+	    stream->periods == periods)
+		return 0; /* not changed */
+
+	au1000_release_dma_link(stream);
+
+	stream->period_size = period_bytes;
+	stream->periods = periods;
+
+	stream->buffer = kmalloc(sizeof(struct pcm_period), GFP_KERNEL);
+	if (!stream->buffer)
+		return -ENOMEM;
+	pointer = stream->buffer;
+	for (i = 0; i < periods; i++) {
+		pointer->start = (u32)(dma_start + (i * period_bytes));
+		pointer->relative_end = (u32) (((i+1) * period_bytes) - 0x1);
+		if (i < periods - 1) {
+			pointer->next = kmalloc(sizeof(struct pcm_period),
+						GFP_KERNEL);
+			if (!pointer->next) {
+				au1000_release_dma_link(stream);
+				return -ENOMEM;
+			}
+			pointer = pointer->next;
+		}
+	}
+	pointer->next = stream->buffer;
+	return 0;
+}
+
+static void au1000_dma_stop(struct audio_stream *stream)
+{
+	if (stream->buffer)
+		disable_dma(stream->dma);
+}
+
+static void au1000_dma_start(struct audio_stream *stream)
+{
+	if (!stream->buffer)
+		return;
+
+	init_dma(stream->dma);
+	if (get_dma_active_buffer(stream->dma) == 0) {
+		clear_dma_done0(stream->dma);
+		set_dma_addr0(stream->dma, stream->buffer->start);
+		set_dma_count0(stream->dma, stream->period_size >> 1);
+		set_dma_addr1(stream->dma, stream->buffer->next->start);
+		set_dma_count1(stream->dma, stream->period_size >> 1);
+	} else {
+		clear_dma_done1(stream->dma);
+		set_dma_addr1(stream->dma, stream->buffer->start);
+		set_dma_count1(stream->dma, stream->period_size >> 1);
+		set_dma_addr0(stream->dma, stream->buffer->next->start);
+		set_dma_count0(stream->dma, stream->period_size >> 1);
+	}
+	enable_dma_buffers(stream->dma);
+	start_dma(stream->dma);
+}
+
+static irqreturn_t au1000_dma_interrupt(int irq, void *ptr)
+{
+	struct audio_stream *stream = (struct audio_stream *)ptr;
+	struct snd_pcm_substream *substream = stream->substream;
+
+	switch (get_dma_buffer_done(stream->dma)) {
+	case DMA_D0:
+		stream->buffer = stream->buffer->next;
+		clear_dma_done0(stream->dma);
+		set_dma_addr0(stream->dma, stream->buffer->next->start);
+		set_dma_count0(stream->dma, stream->period_size >> 1);
+		enable_dma_buffer0(stream->dma);
+		break;
+	case DMA_D1:
+		stream->buffer = stream->buffer->next;
+		clear_dma_done1(stream->dma);
+		set_dma_addr1(stream->dma, stream->buffer->next->start);
+		set_dma_count1(stream->dma, stream->period_size >> 1);
+		enable_dma_buffer1(stream->dma);
+		break;
+	case (DMA_D0 | DMA_D1):
+		pr_debug("DMA %d missed interrupt.\n", stream->dma);
+		au1000_dma_stop(stream);
+		au1000_dma_start(stream);
+		break;
+	case (~DMA_D0 & ~DMA_D1):
+		pr_debug("DMA %d empty irq.\n", stream->dma);
+	}
+	snd_pcm_period_elapsed(substream);
+	return IRQ_HANDLED;
+}
+
+static const struct snd_pcm_hardware alchemy_pcm_hardware = {
+	.info		  = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
+			    SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BATCH,
+	.period_bytes_min = 1024,
+	.period_bytes_max = 16 * 1024 - 1,
+	.periods_min	  = 4,
+	.periods_max	  = 255,
+	.buffer_bytes_max = 128 * 1024,
+	.fifo_size	  = 16,
+};
+
+static inline struct alchemy_pcm_ctx *ss_to_ctx(struct snd_pcm_substream *ss)
+{
+	struct snd_soc_pcm_runtime *rtd = ss->private_data;
+	return snd_soc_platform_get_drvdata(rtd->platform);
+}
+
+static inline struct audio_stream *ss_to_as(struct snd_pcm_substream *ss)
+{
+	struct alchemy_pcm_ctx *ctx = ss_to_ctx(ss);
+	return &(ctx->stream[ss->stream]);
+}
+
+static int alchemy_pcm_open(struct snd_pcm_substream *substream)
+{
+	struct alchemy_pcm_ctx *ctx = ss_to_ctx(substream);
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	int *dmaids, s = substream->stream;
+	char *name;
+
+	dmaids = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
+	if (!dmaids)
+		return -ENODEV;	/* whoa, has ordering changed? */
+
+	/* DMA setup */
+	name = (s == SNDRV_PCM_STREAM_PLAYBACK) ? "audio-tx" : "audio-rx";
+	ctx->stream[s].dma = request_au1000_dma(dmaids[s], name,
+					au1000_dma_interrupt, 0,
+					&ctx->stream[s]);
+	set_dma_mode(ctx->stream[s].dma,
+		     get_dma_mode(ctx->stream[s].dma) & ~DMA_NC);
+
+	ctx->stream[s].substream = substream;
+	ctx->stream[s].buffer = NULL;
+	snd_soc_set_runtime_hwparams(substream, &alchemy_pcm_hardware);
+
+	return 0;
+}
+
+static int alchemy_pcm_close(struct snd_pcm_substream *substream)
+{
+	struct alchemy_pcm_ctx *ctx = ss_to_ctx(substream);
+	int stype = substream->stream;
+
+	ctx->stream[stype].substream = NULL;
+	free_au1000_dma(ctx->stream[stype].dma);
+
+	return 0;
+}
+
+static int alchemy_pcm_hw_params(struct snd_pcm_substream *substream,
+				 struct snd_pcm_hw_params *hw_params)
+{
+	struct audio_stream *stream = ss_to_as(substream);
+	int err;
+
+	err = snd_pcm_lib_malloc_pages(substream,
+				       params_buffer_bytes(hw_params));
+	if (err < 0)
+		return err;
+	err = au1000_setup_dma_link(stream,
+				    params_period_bytes(hw_params),
+				    params_periods(hw_params));
+	if (err)
+		snd_pcm_lib_free_pages(substream);
+
+	return err;
+}
+
+static int alchemy_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+	struct audio_stream *stream = ss_to_as(substream);
+	au1000_release_dma_link(stream);
+	return snd_pcm_lib_free_pages(substream);
+}
+
+static int alchemy_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct audio_stream *stream = ss_to_as(substream);
+	int err = 0;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		au1000_dma_start(stream);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+		au1000_dma_stop(stream);
+		break;
+	default:
+		err = -EINVAL;
+		break;
+	}
+	return err;
+}
+
+static snd_pcm_uframes_t alchemy_pcm_pointer(struct snd_pcm_substream *ss)
+{
+	struct audio_stream *stream = ss_to_as(ss);
+	long location;
+
+	location = get_dma_residue(stream->dma);
+	location = stream->buffer->relative_end - location;
+	if (location == -1)
+		location = 0;
+	return bytes_to_frames(ss->runtime, location);
+}
+
+static struct snd_pcm_ops alchemy_pcm_ops = {
+	.open			= alchemy_pcm_open,
+	.close			= alchemy_pcm_close,
+	.ioctl			= snd_pcm_lib_ioctl,
+	.hw_params	        = alchemy_pcm_hw_params,
+	.hw_free	        = alchemy_pcm_hw_free,
+	.trigger		= alchemy_pcm_trigger,
+	.pointer		= alchemy_pcm_pointer,
+};
+
+static int alchemy_pcm_new(struct snd_soc_pcm_runtime *rtd)
+{
+	struct snd_pcm *pcm = rtd->pcm;
+
+	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
+		snd_dma_continuous_data(GFP_KERNEL), 65536, (4096 * 1024) - 1);
+
+	return 0;
+}
+
+static struct snd_soc_platform_driver alchemy_pcm_soc_platform = {
+	.ops		= &alchemy_pcm_ops,
+	.pcm_new	= alchemy_pcm_new,
+};
+
+static int alchemy_pcm_drvprobe(struct platform_device *pdev)
+{
+	struct alchemy_pcm_ctx *ctx;
+
+	ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, ctx);
+
+	return snd_soc_register_platform(&pdev->dev, &alchemy_pcm_soc_platform);
+}
+
+static int alchemy_pcm_drvremove(struct platform_device *pdev)
+{
+	snd_soc_unregister_platform(&pdev->dev);
+
+	return 0;
+}
+
+static struct platform_driver alchemy_pcmdma_driver = {
+	.driver	= {
+		.name	= "alchemy-pcm-dma",
+	},
+	.probe		= alchemy_pcm_drvprobe,
+	.remove		= alchemy_pcm_drvremove,
+};
+
+module_platform_driver(alchemy_pcmdma_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Au1000/Au1500/Au1100 Audio DMA driver");
+MODULE_AUTHOR("Manuel Lauss");