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
c

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>

show more ...

ASoC: fsl_asrc: Add ASRC ASoC CPU DAI and platform drivers

The Asynchronous Sample Rate Converter (ASRC) converts the sampling rate of a
signal associated with an input clock into a sign

ASoC: fsl_asrc: Add ASRC ASoC CPU DAI and platform drivers

The Asynchronous Sample Rate Converter (ASRC) converts the sampling rate of a
signal associated with an input clock into a signal associated with a different
output clock. The driver currently works as a Front End of DPCM with other Back
Ends DAI links such as ESAI<->CS42888 and SSI<->WM8962 and SAI. It converts the
original sample rate to a common rate supported by Back Ends for playback while
converts the common rate of Back Ends to a desired rate for capture. It has 3
pairs to support three different substreams within totally 10 channels.

Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Reviewed-by: Varka Bhadram <varkabhadram@gmail.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

show more ...