ASoC: fsl_asrc: Don't access members of config before checking it

sound/soc/fsl/fsl_asrc.c:250 fsl_asrc_config_pair()
	warn: variable dereferenced before check 'config' (see line 243)

git remote add next git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
git remote update next
git checkout 3117bb3109
vim +/config +250 sound/soc/fsl/fsl_asrc.c

  237   */
  238  static int fsl_asrc_config_pair(struct fsl_asrc_pair *pair)
  239  {
  240   struct asrc_config *config = pair->config;
  241   struct fsl_asrc *asrc_priv = pair->asrc_priv;
  242   enum asrc_pair_index index = pair->index;
 @243   u32 inrate = config->input_sample_rate, indiv;
  244   u32 outrate = config->output_sample_rate, outdiv;
  245   bool ideal = config->inclk == INCLK_NONE;
  246   u32 clk_index[2], div[2];
  247   int in, out, channels;
  248   struct clk *clk;
  249
 @250   if (!config) {
  251           pair_err("invalid pair config\n");
  252           return -EINVAL;
  253   }

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

sound/soc/fsl/fsl_asrc.c

@@ -240,12 +240,11 @@ static int fsl_asrc_config_pair(struct fsl_asrc_pair *pair)
 	struct asrc_config *config = pair->config;
 	struct fsl_asrc *asrc_priv = pair->asrc_priv;
 	enum asrc_pair_index index = pair->index;
-	u32 inrate = config->input_sample_rate, indiv;
-	u32 outrate = config->output_sample_rate, outdiv;
-	bool ideal = config->inclk == INCLK_NONE;
+	u32 inrate, outrate, indiv, outdiv;
 	u32 clk_index[2], div[2];
 	int in, out, channels;
 	struct clk *clk;
+	bool ideal;
 
 	if (!config) {
 		pair_err("invalid pair config\n");
@@ -264,6 +263,10 @@ static int fsl_asrc_config_pair(struct fsl_asrc_pair *pair)
 		return -EINVAL;
 	}
 
+	inrate = config->input_sample_rate;
+	outrate = config->output_sample_rate;
+	ideal = config->inclk == INCLK_NONE;
+
 	/* Validate input and output sample rates */
 	for (in = 0; in < ARRAY_SIZE(supported_input_rate); in++)
 		if (inrate == supported_input_rate[in])