linux/sound/soc/mxs/mxs-pcm.c
Lars-Peter Clausen 95a771ca16 ASoC: mxs-pcm: Request DMA channel early
Request the DMA channel in the PCM open callback instead of the hwparams
callback, this allows us to let open fail if no dma channel is available. This
also fixes a bug where the channel will be requested multiple times if hwparams
is called multiple times.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-02-22 13:21:49 +00:00

336 lines
8.3 KiB
C

/*
* Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved.
*
* Based on sound/soc/imx/imx-pcm-dma-mx2.c
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/dmaengine.h>
#include <sound/core.h>
#include <sound/initval.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>
#include <mach/dma.h>
#include "mxs-pcm.h"
static struct snd_pcm_hardware snd_mxs_hardware = {
.info = SNDRV_PCM_INFO_MMAP |
SNDRV_PCM_INFO_MMAP_VALID |
SNDRV_PCM_INFO_PAUSE |
SNDRV_PCM_INFO_RESUME |
SNDRV_PCM_INFO_INTERLEAVED,
.formats = SNDRV_PCM_FMTBIT_S16_LE |
SNDRV_PCM_FMTBIT_S20_3LE |
SNDRV_PCM_FMTBIT_S24_LE,
.channels_min = 2,
.channels_max = 2,
.period_bytes_min = 32,
.period_bytes_max = 8192,
.periods_min = 1,
.periods_max = 52,
.buffer_bytes_max = 64 * 1024,
.fifo_size = 32,
};
static void audio_dma_irq(void *data)
{
struct snd_pcm_substream *substream = (struct snd_pcm_substream *)data;
struct snd_pcm_runtime *runtime = substream->runtime;
struct mxs_pcm_runtime_data *iprtd = runtime->private_data;
iprtd->offset += iprtd->period_bytes;
iprtd->offset %= iprtd->period_bytes * iprtd->periods;
snd_pcm_period_elapsed(substream);
}
static bool filter(struct dma_chan *chan, void *param)
{
struct mxs_pcm_runtime_data *iprtd = param;
struct mxs_pcm_dma_params *dma_params = iprtd->dma_params;
if (!mxs_dma_is_apbx(chan))
return false;
if (chan->chan_id != dma_params->chan_num)
return false;
chan->private = &iprtd->dma_data;
return true;
}
static int mxs_dma_alloc(struct snd_pcm_substream *substream)
{
struct snd_soc_pcm_runtime *rtd = substream->private_data;
struct snd_pcm_runtime *runtime = substream->runtime;
struct mxs_pcm_runtime_data *iprtd = runtime->private_data;
dma_cap_mask_t mask;
iprtd->dma_params = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
iprtd->dma_data.chan_irq = iprtd->dma_params->chan_irq;
iprtd->dma_chan = dma_request_channel(mask, filter, iprtd);
if (!iprtd->dma_chan)
return -EINVAL;
return 0;
}
static int snd_mxs_pcm_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct mxs_pcm_runtime_data *iprtd = runtime->private_data;
unsigned long dma_addr;
struct dma_chan *chan;
chan = iprtd->dma_chan;
iprtd->periods = params_periods(params);
iprtd->period_bytes = params_period_bytes(params);
iprtd->offset = 0;
snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
dma_addr = runtime->dma_addr;
iprtd->desc = chan->device->device_prep_dma_cyclic(chan, dma_addr,
iprtd->period_bytes * iprtd->periods,
iprtd->period_bytes,
substream->stream == SNDRV_PCM_STREAM_PLAYBACK ?
DMA_MEM_TO_DEV : DMA_DEV_TO_MEM);
if (!iprtd->desc) {
dev_err(&chan->dev->device, "cannot prepare slave dma\n");
return -EINVAL;
}
iprtd->desc->callback = audio_dma_irq;
iprtd->desc->callback_param = substream;
return 0;
}
static int snd_mxs_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct mxs_pcm_runtime_data *iprtd = runtime->private_data;
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
case SNDRV_PCM_TRIGGER_RESUME:
case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
dmaengine_submit(iprtd->desc);
break;
case SNDRV_PCM_TRIGGER_STOP:
case SNDRV_PCM_TRIGGER_SUSPEND:
case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
dmaengine_terminate_all(iprtd->dma_chan);
break;
default:
return -EINVAL;
}
return 0;
}
static snd_pcm_uframes_t snd_mxs_pcm_pointer(
struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct mxs_pcm_runtime_data *iprtd = runtime->private_data;
return bytes_to_frames(substream->runtime, iprtd->offset);
}
static int snd_mxs_open(struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct mxs_pcm_runtime_data *iprtd;
int ret;
iprtd = kzalloc(sizeof(*iprtd), GFP_KERNEL);
if (iprtd == NULL)
return -ENOMEM;
runtime->private_data = iprtd;
ret = snd_pcm_hw_constraint_integer(substream->runtime,
SNDRV_PCM_HW_PARAM_PERIODS);
if (ret < 0) {
kfree(iprtd);
return ret;
}
ret = mxs_dma_alloc(substream);
if (ret) {
kfree(iprtd);
return ret;
}
snd_soc_set_runtime_hwparams(substream, &snd_mxs_hardware);
return 0;
}
static int snd_mxs_close(struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct mxs_pcm_runtime_data *iprtd = runtime->private_data;
dma_release_channel(iprtd->dma_chan);
kfree(iprtd);
return 0;
}
static int snd_mxs_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 mxs_pcm_ops = {
.open = snd_mxs_open,
.close = snd_mxs_close,
.ioctl = snd_pcm_lib_ioctl,
.hw_params = snd_mxs_pcm_hw_params,
.trigger = snd_mxs_pcm_trigger,
.pointer = snd_mxs_pcm_pointer,
.mmap = snd_mxs_pcm_mmap,
};
static int mxs_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 = snd_mxs_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);
if (!buf->area)
return -ENOMEM;
buf->bytes = size;
return 0;
}
static u64 mxs_pcm_dmamask = DMA_BIT_MASK(32);
static int mxs_pcm_new(struct snd_soc_pcm_runtime *rtd)
{
struct snd_card *card = rtd->card->snd_card;
struct snd_pcm *pcm = rtd->pcm;
int ret = 0;
if (!card->dev->dma_mask)
card->dev->dma_mask = &mxs_pcm_dmamask;
if (!card->dev->coherent_dma_mask)
card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
ret = mxs_pcm_preallocate_dma_buffer(pcm,
SNDRV_PCM_STREAM_PLAYBACK);
if (ret)
goto out;
}
if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
ret = mxs_pcm_preallocate_dma_buffer(pcm,
SNDRV_PCM_STREAM_CAPTURE);
if (ret)
goto out;
}
out:
return ret;
}
static void mxs_pcm_free(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 struct snd_soc_platform_driver mxs_soc_platform = {
.ops = &mxs_pcm_ops,
.pcm_new = mxs_pcm_new,
.pcm_free = mxs_pcm_free,
};
static int __devinit mxs_soc_platform_probe(struct platform_device *pdev)
{
return snd_soc_register_platform(&pdev->dev, &mxs_soc_platform);
}
static int __devexit mxs_soc_platform_remove(struct platform_device *pdev)
{
snd_soc_unregister_platform(&pdev->dev);
return 0;
}
static struct platform_driver mxs_pcm_driver = {
.driver = {
.name = "mxs-pcm-audio",
.owner = THIS_MODULE,
},
.probe = mxs_soc_platform_probe,
.remove = __devexit_p(mxs_soc_platform_remove),
};
module_platform_driver(mxs_pcm_driver);
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:mxs-pcm-audio");