ASoC: sh: fsi: free from NULL pointer of struct sh_fsi_platform_info

Current FSI driver assumed master->info is not NULL.
This patch allow NULL in master->info
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/sh/fsi.c

@@ -113,6 +113,8 @@
 
 #define FSI_FMTS (SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S16_LE)
 
+typedef int (*set_rate_func)(struct device *dev, int is_porta, int rate, int enable);
+
 /*
  * FSI driver use below type name for variable
  *
@@ -269,11 +271,22 @@ static struct fsi_priv *fsi_get_priv(struct snd_pcm_substream *substream)
 	return fsi_get_priv_frm_dai(fsi_get_dai(substream));
 }
 
+static set_rate_func fsi_get_info_set_rate(struct fsi_master *master)
+{
+	if (!master->info)
+		return NULL;
+
+	return master->info->set_rate;
+}
+
 static u32 fsi_get_info_flags(struct fsi_priv *fsi)
 {
 	int is_porta = fsi_is_port_a(fsi);
 	struct fsi_master *master = fsi_get_master(fsi);
 
+	if (!master->info)
+		return 0;
+
 	return is_porta ? master->info->porta_flags :
 		master->info->portb_flags;
 }
@@ -830,12 +843,12 @@ static void fsi_dai_shutdown(struct snd_pcm_substream *substream,
 	struct fsi_priv *fsi = fsi_get_priv(substream);
 	int is_play = fsi_is_play(substream);
 	struct fsi_master *master = fsi_get_master(fsi);
-	int (*set_rate)(struct device *dev, int is_porta, int rate, int enable);
+	set_rate_func set_rate;
 
 	fsi_irq_disable(fsi, is_play);
 	fsi_clk_ctrl(fsi, 0);
 
-	set_rate = master->info->set_rate;
+	set_rate = fsi_get_info_set_rate(master);
 	if (set_rate && fsi->rate)
 		set_rate(dai->dev, fsi_is_port_a(fsi), fsi->rate, 0);
 	fsi->rate = 0;
@@ -902,12 +915,12 @@ static int fsi_dai_hw_params(struct snd_pcm_substream *substream,
 {
 	struct fsi_priv *fsi = fsi_get_priv(substream);
 	struct fsi_master *master = fsi_get_master(fsi);
-	int (*set_rate)(struct device *dev, int is_porta, int rate, int enable);
+	set_rate_func set_rate;
 	int fsi_ver = master->core->ver;
 	long rate = params_rate(params);
 	int ret;
 
-	set_rate = master->info->set_rate;
+	set_rate = fsi_get_info_set_rate(master);
 	if (!set_rate)
 		return 0;