linux/sound/soc/atmel/atmel-pcm-pdc.c
Lars-Peter Clausen 6ed54f08ba ASoC: atmel: Don't set unused struct snd_pcm_hardware fields
The ASoC core assumes that the PCM component of the ASoC card transparently
moves data around and does not impose any restrictions on the memory layout or
the transfer speed. It ignores all fields from the snd_pcm_hardware struct for
the PCM driver that are related to this. Setting these fields in the PCM driver
might suggest otherwise though, so rather not set them.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Bo Shen <voice.shen@atmel.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-01-06 16:45:24 +00:00

401 lines
12 KiB
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,
.period_bytes_min = 32,
.period_bytes_max = 8192,
.periods_min = 2,
.periods_max = 1024,
.buffer_bytes_max = ATMEL_SSC_DMABUF_SIZE,
};
/*--------------------------------------------------------------------------*\
* 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;
};
/*--------------------------------------------------------------------------*\
* 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_warn("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=%zu, period_size=%zu)\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 = %zu\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 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
\*--------------------------------------------------------------------------*/
#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,
.suspend = atmel_pcm_suspend,
.resume = atmel_pcm_resume,
};
int atmel_pcm_pdc_platform_register(struct device *dev)
{
return snd_soc_register_platform(dev, &atmel_soc_platform);
}
EXPORT_SYMBOL(atmel_pcm_pdc_platform_register);
void atmel_pcm_pdc_platform_unregister(struct device *dev)
{
snd_soc_unregister_platform(dev);
}
EXPORT_SYMBOL(atmel_pcm_pdc_platform_unregister);
MODULE_AUTHOR("Sedji Gaouaou <sedji.gaouaou@atmel.com>");
MODULE_DESCRIPTION("Atmel PCM module");
MODULE_LICENSE("GPL");