- 根目录:
- sound
- soc
- atmel
- atmel-pcm.c
/*
* atmel-pcm.c -- ALSA PCM interface for the Atmel atmel SoC.
*
* Copyright (C) 2005 SAN People
* Copyright (C) 2008 Atmel
*
* Authors: Sedji Gaouaou <sedji.gaouaou@atmel.com>
*
* Based on at91-pcm. by:
* Frank Mandarino <fmandarino@endrelia.com>
* Copyright 2006 Endrelia Technologies Inc.
*
* Based on pxa2xx-pcm.c by:
*
* Author: Nicolas Pitre
* Created: Nov 30, 2004
* Copyright: (C) 2004 MontaVista Software, Inc.
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/dma-mapping.h>
#include <linux/atmel_pdc.h>
#include <linux/atmel-ssc.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>
#include "atmel-pcm.h"
/*--------------------------------------------------------------------------*\
* Hardware definition
\*--------------------------------------------------------------------------*/
/* TODO: These values were taken from the AT91 platform driver, check
* them against real values for AT32
*/
static const struct snd_pcm_hardware atmel_pcm_hardware = {
.info = SNDRV_PCM_INFO_MMAP |
SNDRV_PCM_INFO_MMAP_VALID |
SNDRV_PCM_INFO_INTERLEAVED |
SNDRV_PCM_INFO_PAUSE,
.formats = SNDRV_PCM_FMTBIT_S16_LE,
.period_bytes_min = 32,
.period_bytes_max = 8192,
.periods_min = 2,
.periods_max = 1024,
.buffer_bytes_max = 32 * 1024,
};
/*--------------------------------------------------------------------------*\
* Data types
\*--------------------------------------------------------------------------*/
struct atmel_runtime_data {
struct atmel_pcm_dma_params *params;
dma_addr_t dma_buffer; /* physical address of dma buffer */
dma_addr_t dma_buffer_end; /* first address beyond DMA buffer */
size_t period_size;
dma_addr_t period_ptr; /* physical address of next period */
/* PDC register save */
u32 pdc_xpr_save;
u32 pdc_xcr_save;
u32 pdc_xnpr_save;
u32 pdc_xncr_save;
};
/*--------------------------------------------------------------------------*\
* Helper functions
\*--------------------------------------------------------------------------*/
static int atmel_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 = atmel_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_coherent(pcm->card->dev, size,
&buf->addr, GFP_KERNEL);
pr_debug("atmel-pcm:"
"preallocate_dma_buffer: area=%p, addr=%p, size=%d\n",
(void *) buf->area,
(void *) buf->addr,
size);
if (!buf->area)
return -ENOMEM;
buf->bytes = size;
return 0;
}
/*--------------------------------------------------------------------------*\
* ISR
\*--------------------------------------------------------------------------*/
static void atmel_pcm_dma_irq(u32 ssc_sr,
struct snd_pcm_substream *substream)
{
struct atmel_runtime_data *prtd = substream->runtime->private_data;
struct atmel_pcm_dma_params *params = prtd->params;
static int count;
count++;
if (ssc_sr & params->mask->ssc_endbuf) {
pr_warning("atmel-pcm: buffer %s on %s"
" (SSC_SR=%#x, count=%d)\n",
substream->stream == SNDRV_PCM_STREAM_PLAYBACK
? "underrun" : "overrun",
params->name, ssc_sr, count);
/* re-start the PDC */
ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
params->mask->pdc_disable);
prtd->period_ptr += prtd->period_size;
if (prtd->period_ptr >= prtd->dma_buffer_end)
prtd->period_ptr = prtd->dma_buffer;
ssc_writex(params->ssc->regs, params->pdc->xpr,
prtd->period_ptr);
ssc_writex(params->ssc->regs, params->pdc->xcr,
prtd->period_size / params->pdc_xfer_size);
ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
params->mask->pdc_enable);
}
if (ssc_sr & params->mask->ssc_endx) {
/* Load the PDC next pointer and counter registers */
prtd->period_ptr += prtd->period_size;
if (prtd->period_ptr >= prtd->dma_buffer_end)
prtd->period_ptr = prtd->dma_buffer;
ssc_writex(params->ssc->regs, params->pdc->xnpr,
prtd->period_ptr);
ssc_writex(params->ssc->regs, params->pdc->xncr,
prtd->period_size / params->pdc_xfer_size);
}
snd_pcm_period_elapsed(substream);
}
/*--------------------------------------------------------------------------*\
* PCM operations
\*--------------------------------------------------------------------------*/
static int atmel_pcm_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct atmel_runtime_data *prtd = runtime->private_data;
struct snd_soc_pcm_runtime *rtd = substream->private_data;
/* this may get called several times by oss emulation
* with different params */
snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
runtime->dma_bytes = params_buffer_bytes(params);
prtd->params = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
prtd->params->dma_intr_handler = atmel_pcm_dma_irq;
prtd->dma_buffer = runtime->dma_addr;
prtd->dma_buffer_end = runtime->dma_addr + runtime->dma_bytes;
prtd->period_size = params_period_bytes(params);
pr_debug("atmel-pcm: "
"hw_params: DMA for %s initialized "
"(dma_bytes=%u, period_size=%u)\n",
prtd->params->name,
runtime->dma_bytes,
prtd->period_size);
return 0;
}
static int atmel_pcm_hw_free(struct snd_pcm_substream *substream)
{
struct atmel_runtime_data *prtd = substream->runtime->private_data;
struct atmel_pcm_dma_params *params = prtd->params;
if (params != NULL) {
ssc_writex(params->ssc->regs, SSC_PDC_PTCR,
params->mask->pdc_disable);
prtd->params->dma_intr_handler = NULL;
}
return 0;
}
static int atmel_pcm_prepare(struct snd_pcm_substream *substream)
{
struct atmel_runtime_data *prtd = substream->runtime->private_data;
struct atmel_pcm_dma_params *params = prtd->params;
ssc_writex(params->ssc->regs, SSC_IDR,
params->mask->ssc_endx | params->mask->ssc_endbuf);
ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
params->mask->pdc_disable);
return 0;
}
static int atmel_pcm_trigger(struct snd_pcm_substream *substream,
int cmd)
{
struct snd_pcm_runtime *rtd = substream->runtime;
struct atmel_runtime_data *prtd = rtd->private_data;
struct atmel_pcm_dma_params *params = prtd->params;
int ret = 0;
pr_debug("atmel-pcm:buffer_size = %ld,"
"dma_area = %p, dma_bytes = %u\n",
rtd->buffer_size, rtd->dma_area, rtd->dma_bytes);
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
prtd->period_ptr = prtd->dma_buffer;
ssc_writex(params->ssc->regs, params->pdc->xpr,
prtd->period_ptr);
ssc_writex(params->ssc->regs, params->pdc->xcr,
prtd->period_size / params->pdc_xfer_size);
prtd->period_ptr += prtd->period_size;
ssc_writex(params->ssc->regs, params->pdc->xnpr,
prtd->period_ptr);
ssc_writex(params->ssc->regs, params->pdc->xncr,
prtd->period_size / params->pdc_xfer_size);
pr_debug("atmel-pcm: trigger: "
"period_ptr=%lx, xpr=%u, "
"xcr=%u, xnpr=%u, xncr=%u\n",
(unsigned long)prtd->period_ptr,
ssc_readx(params->ssc->regs, params->pdc->xpr),
ssc_readx(params->ssc->regs, params->pdc->xcr),
ssc_readx(params->ssc->regs, params->pdc->xnpr),
ssc_readx(params->ssc->regs, params->pdc->xncr));
ssc_writex(params->ssc->regs, SSC_IER,
params->mask->ssc_endx | params->mask->ssc_endbuf);
ssc_writex(params->ssc->regs, SSC_PDC_PTCR,
params->mask->pdc_enable);
pr_debug("sr=%u imr=%u\n",
ssc_readx(params->ssc->regs, SSC_SR),
ssc_readx(params->ssc->regs, SSC_IER));
break; /* SNDRV_PCM_TRIGGER_START */
case SNDRV_PCM_TRIGGER_STOP:
case SNDRV_PCM_TRIGGER_SUSPEND:
case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
params->mask->pdc_disable);
break;
case SNDRV_PCM_TRIGGER_RESUME:
case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
params->mask->pdc_enable);
break;
default:
ret = -EINVAL;
}
return ret;
}
static snd_pcm_uframes_t atmel_pcm_pointer(
struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct atmel_runtime_data *prtd = runtime->private_data;
struct atmel_pcm_dma_params *params = prtd->params;
dma_addr_t ptr;
snd_pcm_uframes_t x;
ptr = (dma_addr_t) ssc_readx(params->ssc->regs, params->pdc->xpr);
x = bytes_to_frames(runtime, ptr - prtd->dma_buffer);
if (x == runtime->buffer_size)
x = 0;
return x;
}
static int atmel_pcm_open(struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct atmel_runtime_data *prtd;
int ret = 0;
snd_soc_set_runtime_hwparams(substream, &atmel_pcm_hardware);
/* ensure that buffer size is a multiple of period size */
ret = snd_pcm_hw_constraint_integer(runtime,
SNDRV_PCM_HW_PARAM_PERIODS);
if (ret < 0)
goto out;
prtd = kzalloc(sizeof(struct atmel_runtime_data), GFP_KERNEL);
if (prtd == NULL) {
ret = -ENOMEM;
goto out;
}
runtime->private_data = prtd;
out:
return ret;
}
static int atmel_pcm_close(struct snd_pcm_substream *substream)
{
struct atmel_runtime_data *prtd = substream->runtime->private_data;
kfree(prtd);
return 0;
}
static int atmel_pcm_mmap(struct snd_pcm_substream *substream,
struct vm_area_struct *vma)
{
return remap_pfn_range(vma, vma->vm_start,
substream->dma_buffer.addr >> PAGE_SHIFT,
vma->vm_end - vma->vm_start, vma->vm_page_prot);
}
static struct snd_pcm_ops atmel_pcm_ops = {
.open = atmel_pcm_open,
.close = atmel_pcm_close,
.ioctl = snd_pcm_lib_ioctl,
.hw_params = atmel_pcm_hw_params,
.hw_free = atmel_pcm_hw_free,
.prepare = atmel_pcm_prepare,
.trigger = atmel_pcm_trigger,
.pointer = atmel_pcm_pointer,
.mmap = atmel_pcm_mmap,
};
/*--------------------------------------------------------------------------*\
* ASoC platform driver
\*--------------------------------------------------------------------------*/
static u64 atmel_pcm_dmamask = DMA_BIT_MASK(32);
static int atmel_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 = &atmel_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 = atmel_pcm_preallocate_dma_buffer(pcm,
SNDRV_PCM_STREAM_PLAYBACK);
if (ret)
goto out;
}
if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
pr_debug("atmel-pcm:"
"Allocating PCM capture DMA buffer\n");
ret = atmel_pcm_preallocate_dma_buffer(pcm,
SNDRV_PCM_STREAM_CAPTURE);
if (ret)
goto out;
}
out:
return ret;
}
static void atmel_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_coherent(pcm->card->dev, buf->bytes,
buf->area, buf->addr);
buf->area = NULL;
}
}
#ifdef CONFIG_PM
static int atmel_pcm_suspend(struct snd_soc_dai *dai)
{
struct snd_pcm_runtime *runtime = dai->runtime;
struct atmel_runtime_data *prtd;
struct atmel_pcm_dma_params *params;
if (!runtime)
return 0;
prtd = runtime->private_data;
params = prtd->params;
/* disable the PDC and save the PDC registers */
ssc_writel(params->ssc->regs, PDC_PTCR, params->mask->pdc_disable);
prtd->pdc_xpr_save = ssc_readx(params->ssc->regs, params->pdc->xpr);
prtd->pdc_xcr_save = ssc_readx(params->ssc->regs, params->pdc->xcr);
prtd->pdc_xnpr_save = ssc_readx(params->ssc->regs, params->pdc->xnpr);
prtd->pdc_xncr_save = ssc_readx(params->ssc->regs, params->pdc->xncr);
return 0;
}
static int atmel_pcm_resume(struct snd_soc_dai *dai)
{
struct snd_pcm_runtime *runtime = dai->runtime;
struct atmel_runtime_data *prtd;
struct atmel_pcm_dma_params *params;
if (!runtime)
return 0;
prtd = runtime->private_data;
params = prtd->params;
/* restore the PDC registers and enable the PDC */
ssc_writex(params->ssc->regs, params->pdc->xpr, prtd->pdc_xpr_save);
ssc_writex(params->ssc->regs, params->pdc->xcr, prtd->pdc_xcr_save);
ssc_writex(params->ssc->regs, params->pdc->xnpr, prtd->pdc_xnpr_save);
ssc_writex(params->ssc->regs, params->pdc->xncr, prtd->pdc_xncr_save);
ssc_writel(params->ssc->regs, PDC_PTCR, params->mask->pdc_enable);
return 0;
}
#else
#define atmel_pcm_suspend NULL
#define atmel_pcm_resume NULL
#endif
static struct snd_soc_platform_driver atmel_soc_platform = {
.ops = &atmel_pcm_ops,
.pcm_new = atmel_pcm_new,
.pcm_free = atmel_pcm_free_dma_buffers,
.suspend = atmel_pcm_suspend,
.resume = atmel_pcm_resume,
};
static int __devinit atmel_soc_platform_probe(struct platform_device *pdev)
{
return snd_soc_register_platform(&pdev->dev, &atmel_soc_platform);
}
static int __devexit atmel_soc_platform_remove(struct platform_device *pdev)
{
snd_soc_unregister_platform(&pdev->dev);
return 0;
}
static struct platform_driver atmel_pcm_driver = {
.driver = {
.name = "atmel-pcm-audio",
.owner = THIS_MODULE,
},
.probe = atmel_soc_platform_probe,
.remove = __devexit_p(atmel_soc_platform_remove),
};
module_platform_driver(atmel_pcm_driver);
MODULE_AUTHOR("Sedji Gaouaou <sedji.gaouaou@atmel.com>");
MODULE_DESCRIPTION("Atmel PCM module");
MODULE_LICENSE("GPL");