[PATCH v2] ASoC: max9867: shutdown codec when changing filter type

[Pavel Dobias]

Changing filter type without disabling codec results in filter
malfunction. Disable codec when changing filter type.

Signed-off-by: Pavel Dobias <dobias at 2n.cz>
---
Changes in v2:
- don't allow change if component active
- avoid codec shutdown in max9867_filter_set if value not changed

 sound/soc/codecs/max9867.c | 80 +++++++++++++++++++++++++++++++++-----
 sound/soc/codecs/max9867.h |  4 +-
 2 files changed, 73 insertions(+), 11 deletions(-)

diff --git a/sound/soc/codecs/max9867.c b/sound/soc/codecs/max9867.c
index fcb31144d69c..749de1ab1093 100644
--- a/sound/soc/codecs/max9867.c
+++ b/sound/soc/codecs/max9867.c
@@ -15,6 +15,13 @@
 #include <sound/tlv.h>
 #include "max9867.h"
 
+struct max9867_priv {
+	struct regmap *regmap;
+	const struct snd_pcm_hw_constraint_list *constraints;
+	unsigned int sysclk, pclk;
+	bool master, dsp_a;
+};
+
 static const char *const max9867_spmode[] = {
 	"Stereo Diff", "Mono Diff",
 	"Stereo Cap", "Mono Cap",
@@ -32,8 +39,68 @@ static const char *const max9867_adc_dac_filter_text[] = {
 	"Butterworth/8-24"
 };
 
-static SOC_ENUM_SINGLE_DECL(max9867_filter, MAX9867_CODECFLTR, 7,
-	max9867_filter_text);
+static int max9867_filter_get(struct snd_kcontrol *kcontrol,
+			      struct snd_ctl_elem_value *ucontrol)
+{
+	struct snd_soc_component *component = snd_soc_kcontrol_component(kcontrol);
+	struct max9867_priv *max9867 = snd_soc_component_get_drvdata(component);
+	unsigned int reg;
+	int ret;
+
+	ret = regmap_read(max9867->regmap, MAX9867_CODECFLTR, &reg);
+	if (ret)
+		return -EINVAL;
+
+	if (reg & MAX9867_CODECFLTR_MODE)
+		ucontrol->value.enumerated.item[0] = 1;
+	else
+		ucontrol->value.enumerated.item[0] = 0;
+
+	return 0;
+}
+
+static int max9867_filter_set(struct snd_kcontrol *kcontrol,
+			      struct snd_ctl_elem_value *ucontrol)
+{
+	struct snd_soc_component *component = snd_soc_kcontrol_component(kcontrol);
+	struct max9867_priv *max9867 = snd_soc_component_get_drvdata(component);
+	unsigned int reg, mode = ucontrol->value.enumerated.item[0];
+	int ret;
+
+	/* don't allow change if component active */
+	if (snd_soc_component_active(component)) {
+		return -EBUSY;
+	}
+
+	if (mode > 1)
+		return -EINVAL;
+	mode = mode ? MAX9867_CODECFLTR_MODE : 0;
+
+	/* read current filter mode */
+	ret = regmap_read(max9867->regmap, MAX9867_CODECFLTR, &reg);
+	if (ret)
+		return -EINVAL;
+
+	/* check if change is needed */
+	if ((reg & MAX9867_CODECFLTR_MODE) == mode)
+		return 0;
+
+	/* shutdown codec before switching filter mode */
+	regmap_update_bits(max9867->regmap, MAX9867_PWRMAN,
+		MAX9867_PWRMAN_SHDN, 0);
+
+	/* switch filter mode */
+	regmap_update_bits(max9867->regmap, MAX9867_CODECFLTR,
+		MAX9867_CODECFLTR_MODE, mode);
+
+	/* out of shutdown now */
+	regmap_update_bits(max9867->regmap, MAX9867_PWRMAN,
+		MAX9867_PWRMAN_SHDN, MAX9867_PWRMAN_SHDN);
+
+	return 0;
+}
+
+static SOC_ENUM_SINGLE_EXT_DECL(max9867_filter, max9867_filter_text);
 static SOC_ENUM_SINGLE_DECL(max9867_dac_filter, MAX9867_CODECFLTR, 0,
 	max9867_adc_dac_filter_text);
 static SOC_ENUM_SINGLE_DECL(max9867_adc_filter, MAX9867_CODECFLTR, 4,
@@ -76,7 +143,7 @@ static const struct snd_kcontrol_new max9867_snd_controls[] = {
 	SOC_ENUM("Speaker Mode", max9867_spkmode),
 	SOC_SINGLE("Volume Smoothing Switch", MAX9867_MODECONFIG, 6, 1, 0),
 	SOC_SINGLE("Line ZC Switch", MAX9867_MODECONFIG, 5, 1, 0),
-	SOC_ENUM("DSP Filter", max9867_filter),
+	SOC_ENUM_EXT("DSP Filter", max9867_filter, max9867_filter_get, max9867_filter_set),
 	SOC_ENUM("ADC Filter", max9867_adc_filter),
 	SOC_ENUM("DAC Filter", max9867_dac_filter),
 	SOC_SINGLE("Mono Playback Switch", MAX9867_IFC1B, 3, 1, 0),
@@ -197,13 +264,6 @@ static const struct snd_pcm_hw_constraint_list max9867_constraints_48k = {
 	.count = ARRAY_SIZE(max9867_rates_48k),
 };
 
-struct max9867_priv {
-	struct regmap *regmap;
-	const struct snd_pcm_hw_constraint_list *constraints;
-	unsigned int sysclk, pclk;
-	bool master, dsp_a;
-};
-
 static int max9867_startup(struct snd_pcm_substream *substream,
 			   struct snd_soc_dai *dai)
 {
diff --git a/sound/soc/codecs/max9867.h b/sound/soc/codecs/max9867.h
index 3092c3b99075..b6b880631b13 100644
--- a/sound/soc/codecs/max9867.h
+++ b/sound/soc/codecs/max9867.h
@@ -44,7 +44,8 @@
 #define MAX9867_IFC1B_PCLK_4	0x05
 #define MAX9867_IFC1B_PCLK_8	0x06
 #define MAX9867_IFC1B_PCLK_16	0x07
-#define MAX9867_CODECFLTR    0x0a
+#define MAX9867_CODECFLTR	0x0a
+#define MAX9867_CODECFLTR_MODE	(1<<7)
 #define MAX9867_SIDETONE     0x0b
 #define MAX9867_DACLEVEL     0x0c
 #define MAX9867_ADCLEVEL     0x0d
@@ -58,6 +59,7 @@
 #define MAX9867_MICCONFIG    0x15
 #define MAX9867_MODECONFIG   0x16
 #define MAX9867_PWRMAN       0x17
+#define MAX9867_PWRMAN_SHDN  (1<<7)
 #define MAX9867_REVISION     0xff
 
 #define MAX9867_CACHEREGNUM 10
-- 
2.20.1