ASoC: ep93xx i2s audio driver

Add ep93xx i2s audio driver

Signed-off-by: Ryan Mallon <ryan@bluewatersys.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 319 insertions, 0 deletions

diff --git a/sound/soc/ep93xx/ep93xx-pcm.c b/sound/soc/ep93xx/ep93xx-pcm.c
new file mode 100644
index 000000000000..4ba938400791
--- /dev/null
+++ b/sound/soc/ep93xx/ep93xx-pcm.c
@@ -0,0 +1,319 @@
+/*
+ * linux/sound/arm/ep93xx-pcm.c - EP93xx ALSA PCM interface
+ *
+ * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
+ * Copyright (C) 2006 Applied Data Systems
+ *
+ * Rewritten for the SoC audio subsystem (Based on PXA2xx code):
+ *   Copyright (c) 2008 Ryan Mallon <ryan@bluewatersys.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/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 <mach/dma.h>
+#include <mach/hardware.h>
+#include <mach/ep93xx-regs.h>
+
+#include "ep93xx-pcm.h"
+
+static const struct snd_pcm_hardware ep93xx_pcm_hardware = {
+	.info			= (SNDRV_PCM_INFO_MMAP		|
+				   SNDRV_PCM_INFO_MMAP_VALID	|
+				   SNDRV_PCM_INFO_INTERLEAVED	|
+				   SNDRV_PCM_INFO_BLOCK_TRANSFER),
+				   
+	.rates			= SNDRV_PCM_RATE_8000_48000,
+	.rate_min		= SNDRV_PCM_RATE_8000,
+	.rate_max		= SNDRV_PCM_RATE_48000,
+	
+	.formats		= (SNDRV_PCM_FMTBIT_S16_LE |
+				   SNDRV_PCM_FMTBIT_S24_LE |
+				   SNDRV_PCM_FMTBIT_S32_LE),
+	
+	.buffer_bytes_max	= 131072,
+	.period_bytes_min	= 32,
+	.period_bytes_max	= 32768,
+	.periods_min		= 1,
+	.periods_max		= 32,
+	.fifo_size		= 32,
+};
+
+struct ep93xx_runtime_data
+{
+	struct ep93xx_dma_m2p_client	cl;
+	struct ep93xx_pcm_dma_params	*params;
+	int				pointer_bytes;
+	struct tasklet_struct		period_tasklet;
+	int				periods;
+	struct ep93xx_dma_buffer	buf[32];
+};
+
+static void ep93xx_pcm_period_elapsed(unsigned long data)
+{
+	struct snd_pcm_substream *substream = (struct snd_pcm_substream *)data;
+	snd_pcm_period_elapsed(substream);
+}
+
+static void ep93xx_pcm_buffer_started(void *cookie,
+				      struct ep93xx_dma_buffer *buf)
+{
+}
+
+static void ep93xx_pcm_buffer_finished(void *cookie, 
+				       struct ep93xx_dma_buffer *buf, 
+				       int bytes, int error)
+{
+	struct snd_pcm_substream *substream = cookie;
+	struct ep93xx_runtime_data *rtd = substream->runtime->private_data;
+
+	if (buf == rtd->buf + rtd->periods - 1)
+		rtd->pointer_bytes = 0;
+	else
+		rtd->pointer_bytes += buf->size;
+
+	if (!error) {
+		ep93xx_dma_m2p_submit_recursive(&rtd->cl, buf);
+		tasklet_schedule(&rtd->period_tasklet);
+	} else {
+		snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
+	}
+}
+
+static int ep93xx_pcm_open(struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *soc_rtd = substream->private_data;
+	struct snd_soc_dai *cpu_dai = soc_rtd->dai->cpu_dai;
+	struct ep93xx_pcm_dma_params *dma_params;
+	struct ep93xx_runtime_data *rtd;    
+	int ret;
+
+	dma_params = snd_soc_dai_get_dma_data(cpu_dai, substream);
+	snd_soc_set_runtime_hwparams(substream, &ep93xx_pcm_hardware);
+
+	rtd = kmalloc(sizeof(*rtd), GFP_KERNEL);
+	if (!rtd) 
+		return -ENOMEM;
+
+	memset(&rtd->period_tasklet, 0, sizeof(rtd->period_tasklet));
+	rtd->period_tasklet.func = ep93xx_pcm_period_elapsed;
+	rtd->period_tasklet.data = (unsigned long)substream;
+
+	rtd->cl.name = dma_params->name;
+	rtd->cl.flags = dma_params->dma_port | EP93XX_DMA_M2P_IGNORE_ERROR |
+		((substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
+		 EP93XX_DMA_M2P_TX : EP93XX_DMA_M2P_RX);
+	rtd->cl.cookie = substream;
+	rtd->cl.buffer_started = ep93xx_pcm_buffer_started;
+	rtd->cl.buffer_finished = ep93xx_pcm_buffer_finished;
+	ret = ep93xx_dma_m2p_client_register(&rtd->cl);
+	if (ret < 0) {
+		kfree(rtd);
+		return ret;
+	}
+	
+	substream->runtime->private_data = rtd;
+	return 0;
+}
+
+static int ep93xx_pcm_close(struct snd_pcm_substream *substream)
+{
+	struct ep93xx_runtime_data *rtd = substream->runtime->private_data;
+
+	ep93xx_dma_m2p_client_unregister(&rtd->cl);
+	kfree(rtd);
+	return 0;
+}
+
+static int ep93xx_pcm_hw_params(struct snd_pcm_substream *substream,
+				struct snd_pcm_hw_params *params)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct ep93xx_runtime_data *rtd = runtime->private_data;
+	size_t totsize = params_buffer_bytes(params);
+	size_t period = params_period_bytes(params);
+	int i;
+
+	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
+	runtime->dma_bytes = totsize;
+
+	rtd->periods = (totsize + period - 1) / period;
+	for (i = 0; i < rtd->periods; i++) {
+		rtd->buf[i].bus_addr = runtime->dma_addr + (i * period);
+		rtd->buf[i].size = period;
+		if ((i + 1) * period > totsize)
+			rtd->buf[i].size = totsize - (i * period);
+	}
+
+	return 0;
+}
+
+static int ep93xx_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+	snd_pcm_set_runtime_buffer(substream, NULL);
+	return 0;
+}
+
+static int ep93xx_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct ep93xx_runtime_data *rtd = substream->runtime->private_data;
+	int ret;
+	int i;
+
+	ret = 0;
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		rtd->pointer_bytes = 0;
+		for (i = 0; i < rtd->periods; i++)
+			ep93xx_dma_m2p_submit(&rtd->cl, rtd->buf + i);
+		break;
+
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		ep93xx_dma_m2p_flush(&rtd->cl);
+		break;
+
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+static snd_pcm_uframes_t ep93xx_pcm_pointer(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct ep93xx_runtime_data *rtd = substream->runtime->private_data;
+
+	/* FIXME: implement this with sub-period granularity */
+	return bytes_to_frames(runtime, rtd->pointer_bytes);
+}
+
+static int ep93xx_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 ep93xx_pcm_ops = {
+	.open		= ep93xx_pcm_open,
+	.close		= ep93xx_pcm_close,
+	.ioctl		= snd_pcm_lib_ioctl,
+	.hw_params	= ep93xx_pcm_hw_params,
+	.hw_free	= ep93xx_pcm_hw_free,
+	.trigger	= ep93xx_pcm_trigger,
+	.pointer	= ep93xx_pcm_pointer,
+	.mmap		= ep93xx_pcm_mmap,
+};
+
+static int ep93xx_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 = ep93xx_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);
+	buf->bytes = size;
+
+	return (buf->area == NULL) ? -ENOMEM : 0;
+}
+
+static void ep93xx_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_writecombine(pcm->card->dev, buf->bytes, buf->area,
+				      buf->addr);
+		buf->area = NULL;
+	}
+}
+
+static u64 ep93xx_pcm_dmamask = 0xffffffff;
+
+static int ep93xx_pcm_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 = &ep93xx_pcm_dmamask;
+	if (!card->dev->coherent_dma_mask)
+		card->dev->coherent_dma_mask = 0xffffffff;
+
+	if (dai->playback.channels_min) {
+		ret = ep93xx_pcm_preallocate_dma_buffer(pcm,
+					SNDRV_PCM_STREAM_PLAYBACK);
+		if (ret)
+			return ret;
+	}
+
+	if (dai->capture.channels_min) {
+		ret = ep93xx_pcm_preallocate_dma_buffer(pcm,
+					SNDRV_PCM_STREAM_CAPTURE);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+struct snd_soc_platform ep93xx_soc_platform = {
+	.name		= "ep93xx-audio",
+	.pcm_ops	= &ep93xx_pcm_ops,
+	.pcm_new	= &ep93xx_pcm_new,
+	.pcm_free	= &ep93xx_pcm_free_dma_buffers,
+};
+EXPORT_SYMBOL_GPL(ep93xx_soc_platform);
+
+static int __init ep93xx_soc_platform_init(void)
+{
+	return snd_soc_register_platform(&ep93xx_soc_platform);
+}
+
+static void __exit ep93xx_soc_platform_exit(void)
+{
+	snd_soc_unregister_platform(&ep93xx_soc_platform);
+}
+
+module_init(ep93xx_soc_platform_init);
+module_exit(ep93xx_soc_platform_exit);
+
+MODULE_AUTHOR("Ryan Mallon <ryan@bluewatersys.com>");
+MODULE_DESCRIPTION("EP93xx ALSA PCM interface");
+MODULE_LICENSE("GPL");