dma: fsl-edma: fix static checker warning of NULL dereference

The static checker reports following warning:
	drivers/dma/fsl-edma.c:732 fsl_edma_xlate()
	error: we previously assumed 'chan' could be null (see line 737)
The changes of the loop cursor in the iteration may result in
NULL dereference when dma_get_slave_channel failed but loop
will continue. So use list_for_each_entry_safe() instead of
list_for_each_entry() to against this.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jingchang Lu <b35083@freescale.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This commit is contained in:
Jingchang Lu 2014-02-21 14:50:06 +08:00 коммит произвёл Vinod Koul
Родитель 7cbccb55f0
Коммит 178c81e58e
1 изменённых файлов: 2 добавлений и 2 удалений

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@ -723,13 +723,13 @@ static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
struct of_dma *ofdma)
{
struct fsl_edma_engine *fsl_edma = ofdma->of_dma_data;
struct dma_chan *chan;
struct dma_chan *chan, *_chan;
if (dma_spec->args_count != 2)
return NULL;
mutex_lock(&fsl_edma->fsl_edma_mutex);
list_for_each_entry(chan, &fsl_edma->dma_dev.channels, device_node) {
list_for_each_entry_safe(chan, _chan, &fsl_edma->dma_dev.channels, device_node) {
if (chan->client_count)
continue;
if ((chan->chan_id / DMAMUX_NR) == dma_spec->args[0]) {