kernel_optimize_test/sound/soc/fsl/fsl_asrc_dma.c
Nicolin Chen 6ccf62c7be ASoC: fsl_sarc_dma: Check pair before using it
The patch 3117bb3109dc: "ASoC: fsl_asrc: Add ASRC ASoC CPU DAI and
platform drivers" from Jul 29, 2014, leads to the following Smatch
complaint:

sound/soc/fsl/fsl_asrc_dma.c:304 fsl_asrc_dma_shutdown()
warn: variable dereferenced before check 'pair' (see line 302)

sound/soc/fsl/fsl_asrc_dma.c
301          struct fsl_asrc_pair *pair = runtime->private_data;
302          struct fsl_asrc *asrc_priv = pair->asrc_priv;
                                          ^^^^^^^^^^^^^^^
                                            Dereference.

303
304          if (pair && asrc_priv->pair[pair->index] == pair)
                 ^^^^
                Check.

305                  asrc_priv->pair[pair->index] = NULL;
306

So we just let the driver check pair before using it.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-08-04 15:48:41 +01:00

392 lines
11 KiB
C

/*
* Freescale ASRC ALSA SoC Platform (DMA) driver
*
* Copyright (C) 2014 Freescale Semiconductor, Inc.
*
* Author: Nicolin Chen <nicoleotsuka@gmail.com>
*
* This file is licensed under the terms of the GNU General Public License
* version 2. This program is licensed "as is" without any warranty of any
* kind, whether express or implied.
*/
#include <linux/dma-mapping.h>
#include <linux/module.h>
#include <linux/platform_data/dma-imx.h>
#include <sound/dmaengine_pcm.h>
#include <sound/pcm_params.h>
#include "fsl_asrc.h"
#define FSL_ASRC_DMABUF_SIZE (256 * 1024)
static struct snd_pcm_hardware snd_imx_hardware = {
.info = SNDRV_PCM_INFO_INTERLEAVED |
SNDRV_PCM_INFO_BLOCK_TRANSFER |
SNDRV_PCM_INFO_MMAP |
SNDRV_PCM_INFO_MMAP_VALID |
SNDRV_PCM_INFO_PAUSE |
SNDRV_PCM_INFO_RESUME,
.buffer_bytes_max = FSL_ASRC_DMABUF_SIZE,
.period_bytes_min = 128,
.period_bytes_max = 65535, /* Limited by SDMA engine */
.periods_min = 2,
.periods_max = 255,
.fifo_size = 0,
};
static bool filter(struct dma_chan *chan, void *param)
{
if (!imx_dma_is_general_purpose(chan))
return false;
chan->private = param;
return true;
}
static void fsl_asrc_dma_complete(void *arg)
{
struct snd_pcm_substream *substream = arg;
struct snd_pcm_runtime *runtime = substream->runtime;
struct fsl_asrc_pair *pair = runtime->private_data;
pair->pos += snd_pcm_lib_period_bytes(substream);
if (pair->pos >= snd_pcm_lib_buffer_bytes(substream))
pair->pos = 0;
snd_pcm_period_elapsed(substream);
}
static int fsl_asrc_dma_prepare_and_submit(struct snd_pcm_substream *substream)
{
u8 dir = substream->stream == SNDRV_PCM_STREAM_PLAYBACK ? OUT : IN;
struct snd_soc_pcm_runtime *rtd = substream->private_data;
struct snd_pcm_runtime *runtime = substream->runtime;
struct fsl_asrc_pair *pair = runtime->private_data;
struct device *dev = rtd->platform->dev;
unsigned long flags = DMA_CTRL_ACK;
/* Prepare and submit Front-End DMA channel */
if (!substream->runtime->no_period_wakeup)
flags |= DMA_PREP_INTERRUPT;
pair->pos = 0;
pair->desc[!dir] = dmaengine_prep_dma_cyclic(
pair->dma_chan[!dir], runtime->dma_addr,
snd_pcm_lib_buffer_bytes(substream),
snd_pcm_lib_period_bytes(substream),
dir == OUT ? DMA_TO_DEVICE : DMA_FROM_DEVICE, flags);
if (!pair->desc[!dir]) {
dev_err(dev, "failed to prepare slave DMA for Front-End\n");
return -ENOMEM;
}
pair->desc[!dir]->callback = fsl_asrc_dma_complete;
pair->desc[!dir]->callback_param = substream;
dmaengine_submit(pair->desc[!dir]);
/* Prepare and submit Back-End DMA channel */
pair->desc[dir] = dmaengine_prep_dma_cyclic(
pair->dma_chan[dir], 0xffff, 64, 64, DMA_DEV_TO_DEV, 0);
if (!pair->desc[dir]) {
dev_err(dev, "failed to prepare slave DMA for Back-End\n");
return -ENOMEM;
}
dmaengine_submit(pair->desc[dir]);
return 0;
}
static int fsl_asrc_dma_trigger(struct snd_pcm_substream *substream, int cmd)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct fsl_asrc_pair *pair = runtime->private_data;
int ret;
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
case SNDRV_PCM_TRIGGER_RESUME:
case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
ret = fsl_asrc_dma_prepare_and_submit(substream);
if (ret)
return ret;
dma_async_issue_pending(pair->dma_chan[IN]);
dma_async_issue_pending(pair->dma_chan[OUT]);
break;
case SNDRV_PCM_TRIGGER_STOP:
case SNDRV_PCM_TRIGGER_SUSPEND:
case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
dmaengine_terminate_all(pair->dma_chan[OUT]);
dmaengine_terminate_all(pair->dma_chan[IN]);
break;
default:
return -EINVAL;
}
return 0;
}
static int fsl_asrc_dma_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params)
{
enum dma_slave_buswidth buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
struct snd_soc_pcm_runtime *rtd = substream->private_data;
bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
struct snd_dmaengine_dai_dma_data *dma_params_fe = NULL;
struct snd_dmaengine_dai_dma_data *dma_params_be = NULL;
struct snd_pcm_runtime *runtime = substream->runtime;
struct fsl_asrc_pair *pair = runtime->private_data;
struct fsl_asrc *asrc_priv = pair->asrc_priv;
struct dma_slave_config config_fe, config_be;
enum asrc_pair_index index = pair->index;
struct device *dev = rtd->platform->dev;
int stream = substream->stream;
struct imx_dma_data *tmp_data;
struct snd_soc_dpcm *dpcm;
struct dma_chan *tmp_chan;
struct device *dev_be;
u8 dir = tx ? OUT : IN;
dma_cap_mask_t mask;
int ret;
/* Fetch the Back-End dma_data from DPCM */
list_for_each_entry(dpcm, &rtd->dpcm[stream].be_clients, list_be) {
struct snd_soc_pcm_runtime *be = dpcm->be;
struct snd_pcm_substream *substream_be;
struct snd_soc_dai *dai = be->cpu_dai;
if (dpcm->fe != rtd)
continue;
substream_be = snd_soc_dpcm_get_substream(be, stream);
dma_params_be = snd_soc_dai_get_dma_data(dai, substream_be);
dev_be = dai->dev;
break;
}
if (!dma_params_be) {
dev_err(dev, "failed to get the substream of Back-End\n");
return -EINVAL;
}
/* Override dma_data of the Front-End and config its dmaengine */
dma_params_fe = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
dma_params_fe->addr = asrc_priv->paddr + REG_ASRDx(!dir, index);
dma_params_fe->maxburst = dma_params_be->maxburst;
pair->dma_chan[!dir] = fsl_asrc_get_dma_channel(pair, !dir);
if (!pair->dma_chan[!dir]) {
dev_err(dev, "failed to request DMA channel\n");
return -EINVAL;
}
memset(&config_fe, 0, sizeof(config_fe));
ret = snd_dmaengine_pcm_prepare_slave_config(substream, params, &config_fe);
if (ret) {
dev_err(dev, "failed to prepare DMA config for Front-End\n");
return ret;
}
ret = dmaengine_slave_config(pair->dma_chan[!dir], &config_fe);
if (ret) {
dev_err(dev, "failed to config DMA channel for Front-End\n");
return ret;
}
/* Request and config DMA channel for Back-End */
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
dma_cap_set(DMA_CYCLIC, mask);
/* Get DMA request of Back-End */
tmp_chan = dma_request_slave_channel(dev_be, tx ? "tx" : "rx");
tmp_data = tmp_chan->private;
pair->dma_data.dma_request = tmp_data->dma_request;
dma_release_channel(tmp_chan);
/* Get DMA request of Front-End */
tmp_chan = fsl_asrc_get_dma_channel(pair, dir);
tmp_data = tmp_chan->private;
pair->dma_data.dma_request2 = tmp_data->dma_request;
pair->dma_data.peripheral_type = tmp_data->peripheral_type;
pair->dma_data.priority = tmp_data->priority;
dma_release_channel(tmp_chan);
pair->dma_chan[dir] = dma_request_channel(mask, filter, &pair->dma_data);
if (!pair->dma_chan[dir]) {
dev_err(dev, "failed to request DMA channel for Back-End\n");
return -EINVAL;
}
if (asrc_priv->asrc_width == 16)
buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
else
buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
config_be.direction = DMA_DEV_TO_DEV;
config_be.src_addr_width = buswidth;
config_be.src_maxburst = dma_params_be->maxburst;
config_be.dst_addr_width = buswidth;
config_be.dst_maxburst = dma_params_be->maxburst;
if (tx) {
config_be.src_addr = asrc_priv->paddr + REG_ASRDO(index);
config_be.dst_addr = dma_params_be->addr;
} else {
config_be.dst_addr = asrc_priv->paddr + REG_ASRDI(index);
config_be.src_addr = dma_params_be->addr;
}
ret = dmaengine_slave_config(pair->dma_chan[dir], &config_be);
if (ret) {
dev_err(dev, "failed to config DMA channel for Back-End\n");
return ret;
}
snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
return 0;
}
static int fsl_asrc_dma_hw_free(struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct fsl_asrc_pair *pair = runtime->private_data;
snd_pcm_set_runtime_buffer(substream, NULL);
if (pair->dma_chan[IN])
dma_release_channel(pair->dma_chan[IN]);
if (pair->dma_chan[OUT])
dma_release_channel(pair->dma_chan[OUT]);
pair->dma_chan[IN] = NULL;
pair->dma_chan[OUT] = NULL;
return 0;
}
static int fsl_asrc_dma_startup(struct snd_pcm_substream *substream)
{
struct snd_soc_pcm_runtime *rtd = substream->private_data;
struct snd_pcm_runtime *runtime = substream->runtime;
struct device *dev = rtd->platform->dev;
struct fsl_asrc *asrc_priv = dev_get_drvdata(dev);
struct fsl_asrc_pair *pair;
pair = kzalloc(sizeof(struct fsl_asrc_pair), GFP_KERNEL);
if (!pair) {
dev_err(dev, "failed to allocate pair\n");
return -ENOMEM;
}
pair->asrc_priv = asrc_priv;
runtime->private_data = pair;
snd_pcm_hw_constraint_integer(substream->runtime,
SNDRV_PCM_HW_PARAM_PERIODS);
snd_soc_set_runtime_hwparams(substream, &snd_imx_hardware);
return 0;
}
static int fsl_asrc_dma_shutdown(struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct fsl_asrc_pair *pair = runtime->private_data;
struct fsl_asrc *asrc_priv;
if (!pair)
return 0;
asrc_priv = pair->asrc_priv;
if (asrc_priv->pair[pair->index] == pair)
asrc_priv->pair[pair->index] = NULL;
kfree(pair);
return 0;
}
static snd_pcm_uframes_t fsl_asrc_dma_pcm_pointer(struct snd_pcm_substream *substream)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct fsl_asrc_pair *pair = runtime->private_data;
return bytes_to_frames(substream->runtime, pair->pos);
}
static struct snd_pcm_ops fsl_asrc_dma_pcm_ops = {
.ioctl = snd_pcm_lib_ioctl,
.hw_params = fsl_asrc_dma_hw_params,
.hw_free = fsl_asrc_dma_hw_free,
.trigger = fsl_asrc_dma_trigger,
.open = fsl_asrc_dma_startup,
.close = fsl_asrc_dma_shutdown,
.pointer = fsl_asrc_dma_pcm_pointer,
};
static int fsl_asrc_dma_pcm_new(struct snd_soc_pcm_runtime *rtd)
{
struct snd_card *card = rtd->card->snd_card;
struct snd_pcm_substream *substream;
struct snd_pcm *pcm = rtd->pcm;
int ret, i;
ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
if (ret) {
dev_err(card->dev, "failed to set DMA mask\n");
return ret;
}
for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_LAST; i++) {
substream = pcm->streams[i].substream;
if (!substream)
continue;
ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev,
FSL_ASRC_DMABUF_SIZE, &substream->dma_buffer);
if (ret) {
dev_err(card->dev, "failed to allocate DMA buffer\n");
goto err;
}
}
return 0;
err:
if (--i == 0 && pcm->streams[i].substream)
snd_dma_free_pages(&pcm->streams[i].substream->dma_buffer);
return ret;
}
static void fsl_asrc_dma_pcm_free(struct snd_pcm *pcm)
{
struct snd_pcm_substream *substream;
int i;
for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_LAST; i++) {
substream = pcm->streams[i].substream;
if (!substream)
continue;
snd_dma_free_pages(&substream->dma_buffer);
substream->dma_buffer.area = NULL;
substream->dma_buffer.addr = 0;
}
}
struct snd_soc_platform_driver fsl_asrc_platform = {
.ops = &fsl_asrc_dma_pcm_ops,
.pcm_new = fsl_asrc_dma_pcm_new,
.pcm_free = fsl_asrc_dma_pcm_free,
};
EXPORT_SYMBOL_GPL(fsl_asrc_platform);