linux/sound/soc/pxa/pxa2xx-pcm.c
Vasily Khoruzhick 97c96c076b ASoC: PXA: Fix oops in __pxa2xx_pcm_prepare
pxa2xx_pcm_hw_free frees dma channel and sets prtd->dma_ch to -1,
but does not set prtd->params to NULL, so if pxa2xx_pcm_hw_params will
be called immediately, it leaves prtd->dma_ch initialized with -1,
and it results in oops in __pxa2xx_pcm_prepare. This bug is triggered
via SDL.

This patch adds check for prtd->dma_ch to __pxa2xx_pcm_prepare and
cleans prtd->params, so now it works properly.

Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-04-03 18:48:56 +09:00

157 lines
3.8 KiB
C

/*
* linux/sound/arm/pxa2xx-pcm.c -- ALSA PCM interface for the Intel PXA2xx chip
*
* 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 version 2 as
* published by the Free Software Foundation.
*/
#include <linux/dma-mapping.h>
#include <sound/core.h>
#include <sound/soc.h>
#include <sound/pxa2xx-lib.h>
#include "../../arm/pxa2xx-pcm.h"
static int pxa2xx_pcm_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct pxa2xx_runtime_data *prtd = runtime->private_data;
struct snd_soc_pcm_runtime *rtd = substream->private_data;
struct pxa2xx_pcm_dma_params *dma;
int ret;
dma = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
/* 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 */
if (prtd->params == NULL) {
prtd->params = dma;
ret = pxa_request_dma(prtd->params->name, DMA_PRIO_LOW,
pxa2xx_pcm_dma_irq, substream);
if (ret < 0)
return ret;
prtd->dma_ch = ret;
} else if (prtd->params != dma) {
pxa_free_dma(prtd->dma_ch);
prtd->params = dma;
ret = pxa_request_dma(prtd->params->name, DMA_PRIO_LOW,
pxa2xx_pcm_dma_irq, substream);
if (ret < 0)
return ret;
prtd->dma_ch = ret;
}
return __pxa2xx_pcm_hw_params(substream, params);
}
static int pxa2xx_pcm_hw_free(struct snd_pcm_substream *substream)
{
struct pxa2xx_runtime_data *prtd = substream->runtime->private_data;
__pxa2xx_pcm_hw_free(substream);
if (prtd->dma_ch >= 0) {
pxa_free_dma(prtd->dma_ch);
prtd->dma_ch = -1;
prtd->params = NULL;
}
return 0;
}
static struct snd_pcm_ops pxa2xx_pcm_ops = {
.open = __pxa2xx_pcm_open,
.close = __pxa2xx_pcm_close,
.ioctl = snd_pcm_lib_ioctl,
.hw_params = pxa2xx_pcm_hw_params,
.hw_free = pxa2xx_pcm_hw_free,
.prepare = __pxa2xx_pcm_prepare,
.trigger = pxa2xx_pcm_trigger,
.pointer = pxa2xx_pcm_pointer,
.mmap = pxa2xx_pcm_mmap,
};
static u64 pxa2xx_pcm_dmamask = DMA_BIT_MASK(32);
static int pxa2xx_soc_pcm_new(struct snd_card *card, struct snd_soc_dai *dai,
struct snd_pcm *pcm)
{
int ret = 0;
if (!card->dev->dma_mask)
card->dev->dma_mask = &pxa2xx_pcm_dmamask;
if (!card->dev->coherent_dma_mask)
card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
if (dai->driver->playback.channels_min) {
ret = pxa2xx_pcm_preallocate_dma_buffer(pcm,
SNDRV_PCM_STREAM_PLAYBACK);
if (ret)
goto out;
}
if (dai->driver->capture.channels_min) {
ret = pxa2xx_pcm_preallocate_dma_buffer(pcm,
SNDRV_PCM_STREAM_CAPTURE);
if (ret)
goto out;
}
out:
return ret;
}
static struct snd_soc_platform_driver pxa2xx_soc_platform = {
.ops = &pxa2xx_pcm_ops,
.pcm_new = pxa2xx_soc_pcm_new,
.pcm_free = pxa2xx_pcm_free_dma_buffers,
};
static int __devinit pxa2xx_soc_platform_probe(struct platform_device *pdev)
{
return snd_soc_register_platform(&pdev->dev, &pxa2xx_soc_platform);
}
static int __devexit pxa2xx_soc_platform_remove(struct platform_device *pdev)
{
snd_soc_unregister_platform(&pdev->dev);
return 0;
}
static struct platform_driver pxa_pcm_driver = {
.driver = {
.name = "pxa-pcm-audio",
.owner = THIS_MODULE,
},
.probe = pxa2xx_soc_platform_probe,
.remove = __devexit_p(pxa2xx_soc_platform_remove),
};
static int __init snd_pxa_pcm_init(void)
{
return platform_driver_register(&pxa_pcm_driver);
}
module_init(snd_pxa_pcm_init);
static void __exit snd_pxa_pcm_exit(void)
{
platform_driver_unregister(&pxa_pcm_driver);
}
module_exit(snd_pxa_pcm_exit);
MODULE_AUTHOR("Nicolas Pitre");
MODULE_DESCRIPTION("Intel PXA2xx PCM DMA module");
MODULE_LICENSE("GPL");