ASoC: adau17x1: Mark DSP parameter memory as readable and precious

To be able to read back data from the DSP parameter memory the register
range needs to be marked as readable. At the same time we do not want them
to e.g. appear in debugfs output so mark them as precious as well.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/adau1761.c

@@ -793,6 +793,7 @@ const struct regmap_config adau1761_regmap_config = {
 	.num_reg_defaults = ARRAY_SIZE(adau1761_reg_defaults),
 	.readable_reg = adau1761_readable_register,
 	.volatile_reg = adau17x1_volatile_register,
+	.precious_reg = adau17x1_precious_register,
 	.cache_type = REGCACHE_RBTREE,
 };
 EXPORT_SYMBOL_GPL(adau1761_regmap_config);

sound/soc/codecs/adau1781.c

@@ -472,6 +472,7 @@ const struct regmap_config adau1781_regmap_config = {
 	.num_reg_defaults	= ARRAY_SIZE(adau1781_reg_defaults),
 	.readable_reg		= adau1781_readable_register,
 	.volatile_reg		= adau17x1_volatile_register,
+	.precious_reg		= adau17x1_precious_register,
 	.cache_type		= REGCACHE_RBTREE,
 };
 EXPORT_SYMBOL_GPL(adau1781_regmap_config);

sound/soc/codecs/adau17x1.c

@@ -706,8 +706,22 @@ int adau17x1_set_micbias_voltage(struct snd_soc_codec *codec,
 }
 EXPORT_SYMBOL_GPL(adau17x1_set_micbias_voltage);
 
+bool adau17x1_precious_register(struct device *dev, unsigned int reg)
+{
+	/* SigmaDSP parameter memory */
+	if (reg < 0x400)
+		return true;
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(adau17x1_precious_register);
+
 bool adau17x1_readable_register(struct device *dev, unsigned int reg)
 {
+	/* SigmaDSP parameter memory */
+	if (reg < 0x400)
+		return true;
+
 	switch (reg) {
 	case ADAU17X1_CLOCK_CONTROL:
 	case ADAU17X1_PLL_CONTROL:

sound/soc/codecs/adau17x1.h

@@ -56,6 +56,7 @@ int adau17x1_set_micbias_voltage(struct snd_soc_codec *codec,
 	enum adau17x1_micbias_voltage micbias);
 bool adau17x1_readable_register(struct device *dev, unsigned int reg);
 bool adau17x1_volatile_register(struct device *dev, unsigned int reg);
+bool adau17x1_precious_register(struct device *dev, unsigned int reg);
 int adau17x1_resume(struct snd_soc_codec *codec);
 
 extern const struct snd_soc_dai_ops adau17x1_dai_ops;