Linux Kernel iMX6
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 

460 lines
11 KiB

/*
* 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 <linux/module.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,
.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_period;
dma_addr_t dma_start;
dma_addr_t dma_pos;
dma_addr_t dma_end;
struct s3c_dma_params *params;
};
static void audio_buffdone(void *data);
/* 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;
struct samsung_dma_prep dma_info;
pr_debug("Entered %s\n", __func__);
limit = (prtd->dma_end - prtd->dma_start) / prtd->dma_period;
pr_debug("%s: loaded %d, limit %d\n",
__func__, prtd->dma_loaded, limit);
dma_info.cap = (samsung_dma_has_circular() ? DMA_CYCLIC : DMA_SLAVE);
dma_info.direction =
(substream->stream == SNDRV_PCM_STREAM_PLAYBACK
? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM);
dma_info.fp = audio_buffdone;
dma_info.fp_param = substream;
dma_info.period = prtd->dma_period;
dma_info.len = prtd->dma_period*limit;
if (dma_info.cap == DMA_CYCLIC) {
dma_info.buf = pos;
prtd->params->ops->prepare(prtd->params->ch, &dma_info);
prtd->dma_loaded += limit;
return;
}
while (prtd->dma_loaded < limit) {
pr_debug("dma_loaded: %d\n", prtd->dma_loaded);
if ((pos + dma_info.period) > prtd->dma_end) {
dma_info.period = prtd->dma_end - pos;
pr_debug("%s: corrected dma len %ld\n",
__func__, dma_info.period);
}
dma_info.buf = pos;
prtd->params->ops->prepare(prtd->params->ch, &dma_info);
prtd->dma_loaded++;
pos += prtd->dma_period;
if (pos >= prtd->dma_end)
pos = prtd->dma_start;
}
prtd->dma_pos = pos;
}
static void audio_buffdone(void *data)
{
struct snd_pcm_substream *substream = data;
struct runtime_data *prtd = substream->runtime->private_data;
pr_debug("Entered %s\n", __func__);
if (prtd->state & ST_RUNNING) {
prtd->dma_pos += prtd->dma_period;
if (prtd->dma_pos >= prtd->dma_end)
prtd->dma_pos = prtd->dma_start;
if (substream)
snd_pcm_period_elapsed(substream);
spin_lock(&prtd->lock);
if (!samsung_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);
struct samsung_dma_req req;
struct samsung_dma_config config;
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);
prtd->params->ops = samsung_dma_get_ops();
req.cap = (samsung_dma_has_circular() ?
DMA_CYCLIC : DMA_SLAVE);
req.client = prtd->params->client;
config.direction =
(substream->stream == SNDRV_PCM_STREAM_PLAYBACK
? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM);
config.width = prtd->params->dma_size;
config.fifo = prtd->params->dma_addr;
prtd->params->ch = prtd->params->ops->request(
prtd->params->channel, &req, rtd->cpu_dai->dev,
prtd->params->ch_name);
if (!prtd->params->ch) {
pr_err("Failed to allocate DMA channel\n");
return -ENXIO;
}
prtd->params->ops->config(prtd->params->ch, &config);
}
snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
runtime->dma_bytes = totbytes;
spin_lock_irq(&prtd->lock);
prtd->dma_loaded = 0;
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__);
snd_pcm_set_runtime_buffer(substream, NULL);
if (prtd->params) {
prtd->params->ops->flush(prtd->params->ch);
prtd->params->ops->release(prtd->params->ch,
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;
/* flush the DMA channel */
prtd->params->ops->flush(prtd->params->ch);
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:
prtd->state |= ST_RUNNING;
prtd->params->ops->trigger(prtd->params->ch);
break;
case SNDRV_PCM_TRIGGER_STOP:
prtd->state &= ~ST_RUNNING;
prtd->params->ops->stop(prtd->params->ch);
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;
pr_debug("Entered %s\n", __func__);
res = prtd->dma_pos - prtd->dma_start;
pr_debug("Pointer offset: %lu\n", res);
/* 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 int dma_new(struct snd_soc_pcm_runtime *rtd)
{
struct snd_card *card = rtd->card->snd_card;
struct snd_pcm *pcm = rtd->pcm;
int ret;
pr_debug("Entered %s\n", __func__);
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 = preallocate_dma_buffer(pcm,
SNDRV_PCM_STREAM_PLAYBACK);
if (ret)
goto out;
}
if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
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,
};
void samsung_asoc_init_dma_data(struct snd_soc_dai *dai,
struct s3c_dma_params *playback,
struct s3c_dma_params *capture)
{
snd_soc_dai_init_dma_data(dai, playback, capture);
}
EXPORT_SYMBOL_GPL(samsung_asoc_init_dma_data);
int samsung_asoc_dma_platform_register(struct device *dev)
{
return snd_soc_register_platform(dev, &samsung_asoc_platform);
}
EXPORT_SYMBOL_GPL(samsung_asoc_dma_platform_register);
void samsung_asoc_dma_platform_unregister(struct device *dev)
{
snd_soc_unregister_platform(dev);
}
EXPORT_SYMBOL_GPL(samsung_asoc_dma_platform_unregister);
MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
MODULE_DESCRIPTION("Samsung ASoC DMA Driver");
MODULE_LICENSE("GPL");