1 files changed, 488 insertions, 0 deletions

diff --git a/sound/soc/imx/mx1_mx2-pcm.c b/sound/soc/imx/mx1_mx2-pcm.c
new file mode 100644
index 0000000..b838665
--- /dev/null
+++ b/sound/soc/imx/mx1_mx2-pcm.c
@@ -0,0 +1,488 @@
+/*
+ * mx1_mx2-pcm.c -- ALSA SoC interface for Freescale i.MX1x, i.MX2x CPUs
+ *
+ * Copyright 2009 Vista Silicon S.L.
+ * Author: Javier Martin
+ *         javier.martin@vista-silicon.com
+ *
+ * Based on mxc-pcm.c by Liam Girdwood.
+ *
+ * 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/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 <mach/hardware.h>
+#include <mach/dma-mx1-mx2.h>
+
+#include "mx1_mx2-pcm.h"
+
+
+static const struct snd_pcm_hardware mx1_mx2_pcm_hardware = {
+	.info			= (SNDRV_PCM_INFO_INTERLEAVED |
+				   SNDRV_PCM_INFO_BLOCK_TRANSFER |
+				   SNDRV_PCM_INFO_MMAP |
+				   SNDRV_PCM_INFO_MMAP_VALID),
+	.formats		= SNDRV_PCM_FMTBIT_S16_LE,
+	.buffer_bytes_max	= 32 * 1024,
+	.period_bytes_min	= 64,
+	.period_bytes_max	= 8 * 1024,
+	.periods_min		= 2,
+	.periods_max		= 255,
+	.fifo_size		= 0,
+};
+
+struct mx1_mx2_runtime_data {
+	int dma_ch;
+	int active;
+	unsigned int period;
+	unsigned int periods;
+	int tx_spin;
+	spinlock_t dma_lock;
+	struct mx1_mx2_pcm_dma_params *dma_params;
+};
+
+
+/**
+  * This function stops the current dma transfer for playback
+  * and clears the dma pointers.
+  *
+  * @param	substream	pointer to the structure of the current stream.
+  *
+  */
+static int audio_stop_dma(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct mx1_mx2_runtime_data *prtd = runtime->private_data;
+	unsigned long flags;
+
+	spin_lock_irqsave(&prtd->dma_lock, flags);
+
+	pr_debug("%s\n", __func__);
+
+	prtd->active = 0;
+	prtd->period = 0;
+	prtd->periods = 0;
+
+	/* this stops the dma channel and clears the buffer ptrs */
+
+	imx_dma_disable(prtd->dma_ch);
+
+	spin_unlock_irqrestore(&prtd->dma_lock, flags);
+
+	return 0;
+}
+
+/**
+  * This function is called whenever a new audio block needs to be
+  * transferred to the codec. The function receives the address and the size
+  * of the new block and start a new DMA transfer.
+  *
+  * @param	substream	pointer to the structure of the current stream.
+  *
+  */
+static int dma_new_period(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime =  substream->runtime;
+	struct mx1_mx2_runtime_data *prtd = runtime->private_data;
+	unsigned int dma_size;
+	unsigned int offset;
+	int ret = 0;
+	dma_addr_t mem_addr;
+	unsigned int dev_addr;
+
+	if (prtd->active) {
+		dma_size = frames_to_bytes(runtime, runtime->period_size);
+		offset = dma_size * prtd->period;
+
+		pr_debug("%s: period (%d) out of (%d)\n", __func__,
+			prtd->period,
+			runtime->periods);
+		pr_debug("period_size %d frames\n offset %d bytes\n",
+			(unsigned int)runtime->period_size,
+			offset);
+		pr_debug("dma_size %d bytes\n", dma_size);
+
+		snd_BUG_ON(dma_size > mx1_mx2_pcm_hardware.period_bytes_max);
+
+		mem_addr = (dma_addr_t)(runtime->dma_addr + offset);
+		dev_addr = prtd->dma_params->per_address;
+		pr_debug("%s: mem_addr is %x\n dev_addr is %x\n",
+				 __func__, mem_addr, dev_addr);
+
+		ret = imx_dma_setup_single(prtd->dma_ch, mem_addr,
+					dma_size, dev_addr,
+					prtd->dma_params->transfer_type);
+		if (ret < 0) {
+			printk(KERN_ERR "Error %d configuring DMA\n", ret);
+			return ret;
+		}
+		imx_dma_enable(prtd->dma_ch);
+
+		pr_debug("%s: transfer enabled\nmem_addr = %x\n",
+			__func__, (unsigned int) mem_addr);
+		pr_debug("dev_addr = %x\ndma_size = %d\n",
+			(unsigned int) dev_addr, dma_size);
+
+		prtd->tx_spin = 1; /* FGA little trick to retrieve DMA pos */
+		prtd->period++;
+		prtd->period %= runtime->periods;
+    }
+	return ret;
+}
+
+
+/**
+  * This is a callback which will be called
+  * when a TX transfer finishes. The call occurs
+  * in interrupt context.
+  *
+  * @param	dat	pointer to the structure of the current stream.
+  *
+  */
+static void audio_dma_irq(int channel, void *data)
+{
+	struct snd_pcm_substream *substream;
+	struct snd_pcm_runtime *runtime;
+	struct mx1_mx2_runtime_data *prtd;
+	unsigned int dma_size;
+	unsigned int previous_period;
+	unsigned int offset;
+
+	substream = data;
+	runtime = substream->runtime;
+	prtd = runtime->private_data;
+	previous_period  = prtd->periods;
+	dma_size = frames_to_bytes(runtime, runtime->period_size);
+	offset = dma_size * previous_period;
+
+	prtd->tx_spin = 0;
+	prtd->periods++;
+	prtd->periods %= runtime->periods;
+
+	pr_debug("%s: irq per %d offset %x\n", __func__, prtd->periods, offset);
+
+	/*
+	  * If we are getting a callback for an active stream then we inform
+	  * the PCM middle layer we've finished a period
+	  */
+	if (prtd->active)
+		snd_pcm_period_elapsed(substream);
+
+	/*
+	  * Trig next DMA transfer
+	  */
+	dma_new_period(substream);
+}
+
+/**
+  * This function configures the hardware to allow audio
+  * playback operations. It is called by ALSA framework.
+  *
+  * @param	substream	pointer to the structure of the current stream.
+  *
+  * @return              0 on success, -1 otherwise.
+  */
+static int
+snd_mx1_mx2_prepare(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime =  substream->runtime;
+	struct mx1_mx2_runtime_data *prtd = runtime->private_data;
+
+	prtd->period = 0;
+	prtd->periods = 0;
+
+	return 0;
+}
+
+static int mx1_mx2_pcm_hw_params(struct snd_pcm_substream *substream,
+	struct snd_pcm_hw_params *hw_params)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	int ret;
+
+	ret = snd_pcm_lib_malloc_pages(substream,
+					params_buffer_bytes(hw_params));
+	if (ret < 0) {
+		printk(KERN_ERR "%s: Error %d failed to malloc pcm pages \n",
+		__func__, ret);
+		return ret;
+	}
+
+	pr_debug("%s: snd_imx1_mx2_audio_hw_params runtime->dma_addr 0x(%x)\n",
+		__func__, (unsigned int)runtime->dma_addr);
+	pr_debug("%s: snd_imx1_mx2_audio_hw_params runtime->dma_area 0x(%x)\n",
+		__func__, (unsigned int)runtime->dma_area);
+	pr_debug("%s: snd_imx1_mx2_audio_hw_params runtime->dma_bytes 0x(%x)\n",
+		__func__, (unsigned int)runtime->dma_bytes);
+
+	return ret;
+}
+
+static int mx1_mx2_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct mx1_mx2_runtime_data *prtd = runtime->private_data;
+
+	imx_dma_free(prtd->dma_ch);
+
+	snd_pcm_lib_free_pages(substream);
+
+	return 0;
+}
+
+static int mx1_mx2_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct mx1_mx2_runtime_data *prtd = substream->runtime->private_data;
+	int ret = 0;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		prtd->tx_spin = 0;
+		/* requested stream startup */
+		prtd->active = 1;
+		pr_debug("%s: starting dma_new_period\n", __func__);
+		ret = dma_new_period(substream);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+		/* requested stream shutdown */
+		pr_debug("%s: stopping dma transfer\n", __func__);
+		ret = audio_stop_dma(substream);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+static snd_pcm_uframes_t
+mx1_mx2_pcm_pointer(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct mx1_mx2_runtime_data *prtd = runtime->private_data;
+	unsigned int offset = 0;
+
+	/* tx_spin value is used here to check if a transfer is active */
+	if (prtd->tx_spin) {
+		offset = (runtime->period_size * (prtd->periods)) +
+						(runtime->period_size >> 1);
+		if (offset >= runtime->buffer_size)
+			offset = runtime->period_size >> 1;
+	} else {
+		offset = (runtime->period_size * (prtd->periods));
+		if (offset >= runtime->buffer_size)
+			offset = 0;
+	}
+	pr_debug("%s: pointer offset %x\n", __func__, offset);
+
+	return offset;
+}
+
+static int mx1_mx2_pcm_open(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct mx1_mx2_runtime_data *prtd;
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct mx1_mx2_pcm_dma_params *dma_data = rtd->dai->cpu_dai->dma_data;
+	int ret;
+
+	snd_soc_set_runtime_hwparams(substream, &mx1_mx2_pcm_hardware);
+
+	ret = snd_pcm_hw_constraint_integer(runtime,
+					SNDRV_PCM_HW_PARAM_PERIODS);
+	if (ret < 0)
+		return ret;
+
+	prtd = kzalloc(sizeof(struct mx1_mx2_runtime_data), GFP_KERNEL);
+	if (prtd == NULL) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	runtime->private_data = prtd;
+
+	if (!dma_data)
+		return -ENODEV;
+
+	prtd->dma_params = dma_data;
+
+	pr_debug("%s: Requesting dma channel (%s)\n", __func__,
+						prtd->dma_params->name);
+	prtd->dma_ch = imx_dma_request_by_prio(prtd->dma_params->name,
+						DMA_PRIO_HIGH);
+	if (prtd->dma_ch < 0) {
+		printk(KERN_ERR "Error %d requesting dma channel\n", ret);
+		return ret;
+	}
+	imx_dma_config_burstlen(prtd->dma_ch,
+				prtd->dma_params->watermark_level);
+
+	ret = imx_dma_config_channel(prtd->dma_ch,
+			prtd->dma_params->per_config,
+			prtd->dma_params->mem_config,
+			prtd->dma_params->event_id, 0);
+
+	if (ret) {
+		pr_debug(KERN_ERR "Error %d configuring dma channel %d\n",
+			ret, prtd->dma_ch);
+		return ret;
+	}
+
+	pr_debug("%s: Setting tx dma callback function\n", __func__);
+	ret = imx_dma_setup_handlers(prtd->dma_ch,
+				audio_dma_irq, NULL,
+				(void *)substream);
+	if (ret < 0) {
+		printk(KERN_ERR "Error %d setting dma callback function\n", ret);
+		return ret;
+	}
+	return 0;
+
+ out:
+	return ret;
+}
+
+static int mx1_mx2_pcm_close(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct mx1_mx2_runtime_data *prtd = runtime->private_data;
+
+	kfree(prtd);
+
+	return 0;
+}
+
+static int mx1_mx2_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 mx1_mx2_pcm_ops = {
+	.open		= mx1_mx2_pcm_open,
+	.close		= mx1_mx2_pcm_close,
+	.ioctl		= snd_pcm_lib_ioctl,
+	.hw_params	= mx1_mx2_pcm_hw_params,
+	.hw_free	= mx1_mx2_pcm_hw_free,
+	.prepare	= snd_mx1_mx2_prepare,
+	.trigger	= mx1_mx2_pcm_trigger,
+	.pointer	= mx1_mx2_pcm_pointer,
+	.mmap		= mx1_mx2_pcm_mmap,
+};
+
+static u64 mx1_mx2_pcm_dmamask = 0xffffffff;
+
+static int mx1_mx2_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 = mx1_mx2_pcm_hardware.buffer_bytes_max;
+	buf->dev.type = SNDRV_DMA_TYPE_DEV;
+	buf->dev.dev = pcm->card->dev;
+	buf->private_data = NULL;
+
+	/* Reserve uncached-buffered memory area for DMA */
+	buf->area = dma_alloc_writecombine(pcm->card->dev, size,
+					   &buf->addr, GFP_KERNEL);
+
+	pr_debug("%s: preallocate_dma_buffer: area=%p, addr=%p, size=%d\n",
+		__func__, (void *) buf->area, (void *) buf->addr, size);
+
+	if (!buf->area)
+		return -ENOMEM;
+
+	buf->bytes = size;
+	return 0;
+}
+
+static void mx1_mx2_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 int mx1_mx2_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 = &mx1_mx2_pcm_dmamask;
+	if (!card->dev->coherent_dma_mask)
+		card->dev->coherent_dma_mask = 0xffffffff;
+
+	if (dai->playback.channels_min) {
+		ret = mx1_mx2_pcm_preallocate_dma_buffer(pcm,
+			SNDRV_PCM_STREAM_PLAYBACK);
+		pr_debug("%s: preallocate playback buffer\n", __func__);
+		if (ret)
+			goto out;
+	}
+
+	if (dai->capture.channels_min) {
+		ret = mx1_mx2_pcm_preallocate_dma_buffer(pcm,
+			SNDRV_PCM_STREAM_CAPTURE);
+		pr_debug("%s: preallocate capture buffer\n", __func__);
+		if (ret)
+			goto out;
+	}
+ out:
+	return ret;
+}
+
+struct snd_soc_platform mx1_mx2_soc_platform = {
+	.name		= "mx1_mx2-audio",
+	.pcm_ops 	= &mx1_mx2_pcm_ops,
+	.pcm_new	= mx1_mx2_pcm_new,
+	.pcm_free	= mx1_mx2_pcm_free_dma_buffers,
+};
+EXPORT_SYMBOL_GPL(mx1_mx2_soc_platform);
+
+static int __init mx1_mx2_soc_platform_init(void)
+{
+	return snd_soc_register_platform(&mx1_mx2_soc_platform);
+}
+module_init(mx1_mx2_soc_platform_init);
+
+static void __exit mx1_mx2_soc_platform_exit(void)
+{
+	snd_soc_unregister_platform(&mx1_mx2_soc_platform);
+}
+module_exit(mx1_mx2_soc_platform_exit);
+
+MODULE_AUTHOR("Javier Martin, javier.martin@vista-silicon.com");
+MODULE_DESCRIPTION("Freescale i.MX2x, i.MX1x PCM DMA module");
+MODULE_LICENSE("GPL");