[PATCH] ASoC: cs42l42: Add HP Volume Scale control

[Vitaly Rodionov <vitalyr@opensource.cirrus.com>]

From: Richard Fitzgerald <rf@opensource.cirrus.com>

cs42l42 has a configurable scaling of the maximum volume. Add an
ALSA control for this. Note that the datasheet name is "full scale
volume" but this conflicts with ALSA naming convention so the control
is named "HP Volume Scale".

Before this change the FULL_SCALE_VOLUME was set based on the value in
RLA_STAT, but as there isn't any load detection result this always set
the scaling to -6dB instead of the default 0dB.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Signed-off-by: Vitaly Rodionov <vitalyr@opensource.cirrus.com>
---
 sound/soc/codecs/cs42l42.c | 25 ++++++++++++-------------
 1 file changed, 12 insertions(+), 13 deletions(-)

diff --git a/sound/soc/codecs/cs42l42.c b/sound/soc/codecs/cs42l42.c
index d5e1e5228b5f..78f8c89410b6 100644
--- a/sound/soc/codecs/cs42l42.c
+++ b/sound/soc/codecs/cs42l42.c
@@ -425,6 +425,14 @@ static SOC_ENUM_SINGLE_DECL(cs42l42_wnf3_freq_enum, CS42L42_ADC_WNF_HPF_CTL,
 			    CS42L42_ADC_WNF_CF_SHIFT,
 			    cs42l42_wnf3_freq_text);
 
+static const char * const cs42l42_full_scale_vol_text[] = {
+	"0dB", "-6dB"
+};
+
+static SOC_ENUM_SINGLE_DECL(cs42l42_full_scale_vol_enum, CS42L42_HP_CTL,
+			    CS42L42_HP_FULL_SCALE_VOL_SHIFT,
+			    cs42l42_full_scale_vol_text);
+
 static const struct snd_kcontrol_new cs42l42_snd_controls[] = {
 	/* ADC Volume and Filter Controls */
 	SOC_SINGLE("ADC Notch Switch", CS42L42_ADC_CTL,
@@ -450,6 +458,7 @@ static const struct snd_kcontrol_new cs42l42_snd_controls[] = {
 				CS42L42_DACB_INV_SHIFT, true, false),
 	SOC_SINGLE("DAC HPF Switch", CS42L42_DAC_CTL2,
 				CS42L42_DAC_HPF_EN_SHIFT, true, false),
+	SOC_ENUM("HP Volume Scale", cs42l42_full_scale_vol_enum),
 	SOC_DOUBLE_R_TLV("Mixer Volume", CS42L42_MIXER_CHA_VOL,
 			 CS42L42_MIXER_CHB_VOL, CS42L42_MIXER_CH_VOL_SHIFT,
 				0x3f, 1, mixer_tlv)
@@ -922,7 +931,6 @@ static int cs42l42_mute_stream(struct snd_soc_dai *dai, int mute, int stream)
 	struct snd_soc_component *component = dai->component;
 	struct cs42l42_private *cs42l42 = snd_soc_component_get_drvdata(component);
 	unsigned int regval;
-	u8 fullScaleVol;
 	int ret;
 
 	if (mute) {
@@ -993,20 +1001,11 @@ static int cs42l42_mute_stream(struct snd_soc_dai *dai, int mute, int stream)
 		cs42l42->stream_use |= 1 << stream;
 
 		if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
-			/* Read the headphone load */
-			regval = snd_soc_component_read(component, CS42L42_LOAD_DET_RCSTAT);
-			if (((regval & CS42L42_RLA_STAT_MASK) >> CS42L42_RLA_STAT_SHIFT) ==
-			    CS42L42_RLA_STAT_15_OHM) {
-				fullScaleVol = CS42L42_HP_FULL_SCALE_VOL_MASK;
-			} else {
-				fullScaleVol = 0;
-			}
-
-			/* Un-mute the headphone, set the full scale volume flag */
+			/* Un-mute the headphone */
 			snd_soc_component_update_bits(component, CS42L42_HP_CTL,
 						      CS42L42_HP_ANA_AMUTE_MASK |
-						      CS42L42_HP_ANA_BMUTE_MASK |
-						      CS42L42_HP_FULL_SCALE_VOL_MASK, fullScaleVol);
+						      CS42L42_HP_ANA_BMUTE_MASK,
+						      0);
 		}
 	}
 
-- 
2.25.1