ASoC: rt5645: add error checking to rt5645_probe function

Check for return value from various snd_soc_dapm_* calls, as many of
them can return errors and this should be handled. Also, reintroduce
the allocation failure check for rt5645->eq_param as well. Make all
areas where return values are checked lead to the end of the function
in the case of an error. Finally, introduce a comment explaining how
resources here are actually eventually cleaned up by the caller.

Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Phillip Potter <phil@philpotter.co.uk>
Link: https://lore.kernel.org/r/20210503115736.2104747-56-gregkh@linuxfoundation.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

sound/soc/codecs/rt5645.c

@@ -3388,30 +3388,44 @@ static int rt5645_probe(struct snd_soc_component *component)
 {
 	struct snd_soc_dapm_context *dapm = snd_soc_component_get_dapm(component);
 	struct rt5645_priv *rt5645 = snd_soc_component_get_drvdata(component);
+	int ret = 0;
 
 	rt5645->component = component;
 
 	switch (rt5645->codec_type) {
 	case CODEC_TYPE_RT5645:
-		snd_soc_dapm_new_controls(dapm,
+		ret = snd_soc_dapm_new_controls(dapm,
 			rt5645_specific_dapm_widgets,
 			ARRAY_SIZE(rt5645_specific_dapm_widgets));
-		snd_soc_dapm_add_routes(dapm,
+		if (ret < 0)
+			goto exit;
+
+		ret = snd_soc_dapm_add_routes(dapm,
 			rt5645_specific_dapm_routes,
 			ARRAY_SIZE(rt5645_specific_dapm_routes));
+		if (ret < 0)
+			goto exit;
+
 		if (rt5645->v_id < 3) {
-			snd_soc_dapm_add_routes(dapm,
+			ret = snd_soc_dapm_add_routes(dapm,
 				rt5645_old_dapm_routes,
 				ARRAY_SIZE(rt5645_old_dapm_routes));
+			if (ret < 0)
+				goto exit;
 		}
 		break;
 	case CODEC_TYPE_RT5650:
-		snd_soc_dapm_new_controls(dapm,
+		ret = snd_soc_dapm_new_controls(dapm,
 			rt5650_specific_dapm_widgets,
 			ARRAY_SIZE(rt5650_specific_dapm_widgets));
-		snd_soc_dapm_add_routes(dapm,
+		if (ret < 0)
+			goto exit;
+
+		ret = snd_soc_dapm_add_routes(dapm,
 			rt5650_specific_dapm_routes,
 			ARRAY_SIZE(rt5650_specific_dapm_routes));
+		if (ret < 0)
+			goto exit;
 		break;
 	}
 
@@ -3419,9 +3433,17 @@ static int rt5645_probe(struct snd_soc_component *component)
 
 	/* for JD function */
 	if (rt5645->pdata.jd_mode) {
-		snd_soc_dapm_force_enable_pin(dapm, "JD Power");
-		snd_soc_dapm_force_enable_pin(dapm, "LDO2");
-		snd_soc_dapm_sync(dapm);
+		ret = snd_soc_dapm_force_enable_pin(dapm, "JD Power");
+		if (ret < 0)
+			goto exit;
+
+		ret = snd_soc_dapm_force_enable_pin(dapm, "LDO2");
+		if (ret < 0)
+			goto exit;
+
+		ret = snd_soc_dapm_sync(dapm);
+		if (ret < 0)
+			goto exit;
 	}
 
 	if (rt5645->pdata.long_name)
@@ -3431,7 +3453,15 @@ static int rt5645_probe(struct snd_soc_component *component)
 		RT5645_HWEQ_NUM, sizeof(struct rt5645_eq_param_s),
 		GFP_KERNEL);
 
-	return 0;
+	if (!rt5645->eq_param)
+		ret = -ENOMEM;
+exit:
+	/*
+	 * If there was an error above, everything will be cleaned up by the
+	 * caller if we return an error here.  This will be done with a later
+	 * call to rt5645_remove().
+	 */
+	return ret;
 }
 
 static void rt5645_remove(struct snd_soc_component *component)