- 根目录:
- sound
- soc
- samsung
- dma.c
/*
* dma.c -- ALSA Soc Audio Layer
*
* (c) 2006 Wolfson Microelectronics PLC.
* Graeme Gregory graeme.gregory@wolfsonmicro.com or linux@wolfsonmicro.com
*
* Copyright 2004-2005 Simtec Electronics
* http://armlinux.simtec.co.uk/
* Ben Dooks <ben@simtec.co.uk>
*
* 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/slab.h>
#include <linux/dma-mapping.h>
#include <sound/soc.h>
#include <sound/pcm_params.h>
#include <asm/dma.h>
#include <mach/hardware.h>
#include <mach/dma.h>
#include "dma.h"
#define ST_RUNNING (1<<0)
#define ST_OPENED (1<<1)
static const struct snd_pcm_hardware dma_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,
.formats = SNDRV_PCM_FMTBIT_S16_LE |
SNDRV_PCM_FMTBIT_U16_LE |
SNDRV_PCM_FMTBIT_U8 |
SNDRV_PCM_FMTBIT_S8,
.channels_min = 2,
.channels_max = 2,
.buffer_bytes_max = 128*1024,
.period_bytes_min = PAGE_SIZE,
.period_bytes_max = PAGE_SIZE*2,
.periods_min = 2,
.periods_max = 128,
.fifo_size = 32,
};
struct runtime_data {
spinlock_t lock;
int state;
unsigned int dma_loaded;
unsigned int dma_limit;
unsigned int dma_period;
dma_addr_t dma_start;
dma_addr_t dma_pos;
dma_addr_t dma_end;
struct s3c_dma_params *params;
};
/* dma_enqueue
*
* place a dma buffer onto the queue for the dma system
* to handle.
*/
static void dma_enqueue(struct snd_pcm_substream *substream)
{
struct runtime_data *prtd = substream->runtime->private_data;
dma_addr_t pos = prtd->dma_pos;
unsigned int limit;
int ret;
pr_debug("Entered %s\n", __func__);
if (s3c_dma_has_circular())
limit = (prtd->dma_end - prtd->dma_start) / prtd->dma_period;
else
limit = prtd->dma_limit;
pr_debug("%s: loaded %d, limit %d\n",
__func__, prtd->dma_loaded, limit);
while (prtd->dma_loaded < limit) {
unsigned long len = prtd->dma_period;
pr_debug("dma_loaded: %d\n", prtd->dma_loaded);
if ((pos + len) > prtd->dma_end) {
len = prtd->dma_end - pos;
pr_debug("%s: corrected dma len %ld\n", __func__, len);
}
ret = s3c2410_dma_enqueue(prtd->params->channel,
substream, pos, len);
if (ret == 0) {
prtd->dma_loaded++;
pos += prtd->dma_period;
if (pos >= prtd->dma_end)
pos = prtd->dma_start;
} else
break;
}
prtd->dma_pos = pos;
}
static void audio_buffdone(struct s3c2410_dma_chan *channel,
void *dev_id, int size,
enum s3c2410_dma_buffresult result)
{
struct snd_pcm_substream *substream = dev_id;
struct runtime_data *prtd;
pr_debug("Entered %s\n", __func__);
if (result == S3C2410_RES_ABORT || result == S3C2410_RES_ERR)
return;
prtd = substream->runtime->private_data;
if (substream)
snd_pcm_period_elapsed(substream);
spin_lock(&prtd->lock);
if (prtd->state & ST_RUNNING && !s3c_dma_has_circular()) {
prtd->dma_loaded--;
dma_enqueue(substream);
}
spin_unlock(&prtd->lock);
}
static int dma_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct runtime_data *prtd = runtime->private_data;
struct snd_soc_pcm_runtime *rtd = substream->private_data;
unsigned long totbytes = params_buffer_bytes(params);
struct s3c_dma_params *dma =
snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
int ret = 0;
pr_debug("Entered %s\n", __func__);
/* return if this is a bufferless transfer e.g.
* codec <--> BT codec or GSM modem -- lg FIXME */
if (!dma)
return 0;
/* this may get called several times by oss emulation
* with different params -HW */
if (prtd->params == NULL) {
/* prepare DMA */
prtd->params = dma;
pr_debug("params %p, client %p, channel %d\n", prtd->params,
prtd->params->client, prtd->params->channel);
ret = s3c2410_dma_request(prtd->params->channel,
prtd->params->client, NULL);
if (ret < 0) {
printk(KERN_ERR "failed to get dma channel\n");
return ret;
}
/* use the circular buffering if we have it available. */
if (s3c_dma_has_circular())
s3c2410_dma_setflags(prtd->params->channel,
S3C2410_DMAF_CIRCULAR);
}
s3c2410_dma_set_buffdone_fn(prtd->params->channel,
audio_buffdone);
snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
runtime->dma_bytes = totbytes;
spin_lock_irq(&prtd->lock);
prtd->dma_loaded = 0;
prtd->dma_limit = runtime->hw.periods_min;
prtd->dma_period = params_period_bytes(params);
prtd->dma_start = runtime->dma_addr;
prtd->dma_pos = prtd->dma_start;
prtd->dma_end = prtd->dma_start + totbytes;
spin_unlock_irq(&prtd->lock);
return 0;
}
static int dma_hw_free(struct snd_pcm_substream *substream)
{
struct runtime_data *prtd = substream->runtime->private_data;
pr_debug("Entered %s\n", __func__);
/* TODO - do we need to ensure DMA flushed */
snd_pcm_set_runtime_buffer(substream, NULL);
if (prtd->params) {
s3c2410_dma_free(prtd->params->channel, prtd->params->client);
prtd->params = NULL;
}
return 0;
}
static int dma_prepare(struct snd_pcm_substream *substream)
{
struct runtime_data *prtd = substream->runtime->private_data;
int ret = 0;
pr_debug("Entered %s\n", __func__);
/* return if this is a bufferless transfer e.g.
* codec <--> BT codec or GSM modem -- lg FIXME */
if (!prtd->params)
return 0;
/* channel needs configuring for mem=>device, increment memory addr,
* sync to pclk, half-word transfers to the IIS-FIFO. */
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
s3c2410_dma_devconfig(prtd->params->channel,
S3C2410_DMASRC_MEM,
prtd->params->dma_addr);
} else {
s3c2410_dma_devconfig(prtd->params->channel,
S3C2410_DMASRC_HW,
prtd->params->dma_addr);
}
s3c2410_dma_config(prtd->params->channel,
prtd->params->dma_size);
/* flush the DMA channel */
s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_FLUSH);
prtd->dma_loaded = 0;
prtd->dma_pos = prtd->dma_start;
/* enqueue dma buffers */
dma_enqueue(substream);
return ret;
}
static int dma_trigger(struct snd_pcm_substream *substream, int cmd)
{
struct runtime_data *prtd = substream->runtime->private_data;
int ret = 0;
pr_debug("Entered %s\n", __func__);
spin_lock(&prtd->lock);
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
case SNDRV_PCM_TRIGGER_RESUME:
case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
prtd->state |= ST_RUNNING;
s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_START);
break;
case SNDRV_PCM_TRIGGER_STOP:
case SNDRV_PCM_TRIGGER_SUSPEND:
case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
prtd->state &= ~ST_RUNNING;
s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_STOP);
break;
default:
ret = -EINVAL;
break;
}
spin_unlock(&prtd->lock);
return ret;
}
static snd_pcm_uframes_t
dma_pointer(struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct runtime_data *prtd = runtime->private_data;
unsigned long res;
dma_addr_t src, dst;
pr_debug("Entered %s\n", __func__);
spin_lock(&prtd->lock);
s3c2410_dma_getposition(prtd->params->channel, &src, &dst);
if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
res = dst - prtd->dma_start;
else
res = src - prtd->dma_start;
spin_unlock(&prtd->lock);
pr_debug("Pointer %x %x\n", src, dst);
/* we seem to be getting the odd error from the pcm library due
* to out-of-bounds pointers. this is maybe due to the dma engine
* not having loaded the new values for the channel before being
* called... (todo - fix )
*/
if (res >= snd_pcm_lib_buffer_bytes(substream)) {
if (res == snd_pcm_lib_buffer_bytes(substream))
res = 0;
}
return bytes_to_frames(substream->runtime, res);
}
static int dma_open(struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct runtime_data *prtd;
pr_debug("Entered %s\n", __func__);
snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
snd_soc_set_runtime_hwparams(substream, &dma_hardware);
prtd = kzalloc(sizeof(struct runtime_data), GFP_KERNEL);
if (prtd == NULL)
return -ENOMEM;
spin_lock_init(&prtd->lock);
runtime->private_data = prtd;
return 0;
}
static int dma_close(struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct runtime_data *prtd = runtime->private_data;
pr_debug("Entered %s\n", __func__);
if (!prtd)
pr_debug("dma_close called with prtd == NULL\n");
kfree(prtd);
return 0;
}
static int dma_mmap(struct snd_pcm_substream *substream,
struct vm_area_struct *vma)
{
struct snd_pcm_runtime *runtime = substream->runtime;
pr_debug("Entered %s\n", __func__);
return dma_mmap_writecombine(substream->pcm->card->dev, vma,
runtime->dma_area,
runtime->dma_addr,
runtime->dma_bytes);
}
static struct snd_pcm_ops dma_ops = {
.open = dma_open,
.close = dma_close,
.ioctl = snd_pcm_lib_ioctl,
.hw_params = dma_hw_params,
.hw_free = dma_hw_free,
.prepare = dma_prepare,
.trigger = dma_trigger,
.pointer = dma_pointer,
.mmap = dma_mmap,
};
static int 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 = dma_hardware.buffer_bytes_max;
pr_debug("Entered %s\n", __func__);
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 dma_free_dma_buffers(struct snd_pcm *pcm)
{
struct snd_pcm_substream *substream;
struct snd_dma_buffer *buf;
int stream;
pr_debug("Entered %s\n", __func__);
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 dma_mask = DMA_BIT_MASK(32);
static int dma_new(struct snd_card *card,
struct snd_soc_dai *dai, struct snd_pcm *pcm)
{
int ret = 0;
pr_debug("Entered %s\n", __func__);
if (!card->dev->dma_mask)
card->dev->dma_mask = &dma_mask;
if (!card->dev->coherent_dma_mask)
card->dev->coherent_dma_mask = 0xffffffff;
if (dai->driver->playback.channels_min) {
ret = preallocate_dma_buffer(pcm,
SNDRV_PCM_STREAM_PLAYBACK);
if (ret)
goto out;
}
if (dai->driver->capture.channels_min) {
ret = preallocate_dma_buffer(pcm,
SNDRV_PCM_STREAM_CAPTURE);
if (ret)
goto out;
}
out:
return ret;
}
static struct snd_soc_platform_driver samsung_asoc_platform = {
.ops = &dma_ops,
.pcm_new = dma_new,
.pcm_free = dma_free_dma_buffers,
};
static int __devinit samsung_asoc_platform_probe(struct platform_device *pdev)
{
return snd_soc_register_platform(&pdev->dev, &samsung_asoc_platform);
}
static int __devexit samsung_asoc_platform_remove(struct platform_device *pdev)
{
snd_soc_unregister_platform(&pdev->dev);
return 0;
}
static struct platform_driver asoc_dma_driver = {
.driver = {
.name = "samsung-audio",
.owner = THIS_MODULE,
},
.probe = samsung_asoc_platform_probe,
.remove = __devexit_p(samsung_asoc_platform_remove),
};
static int __init samsung_asoc_init(void)
{
return platform_driver_register(&asoc_dma_driver);
}
module_init(samsung_asoc_init);
static void __exit samsung_asoc_exit(void)
{
platform_driver_unregister(&asoc_dma_driver);
}
module_exit(samsung_asoc_exit);
MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
MODULE_DESCRIPTION("Samsung ASoC DMA Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:samsung-audio");