ASoC: rt5640: add Mono ADC Capture Switch control

Mono ADC Capture Switch control is missing in the driver. So, add it.
Signed-off-by: NBard Liao <bardliao@realtek.com>
Tested-by: NPierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

sound/soc/codecs/rt5640.c

@@ -423,6 +423,8 @@ static const struct snd_kcontrol_new rt5640_snd_controls[] = {
 	SOC_DOUBLE_TLV("ADC Capture Volume", RT5640_ADC_DIG_VOL,
 			RT5640_L_VOL_SFT, RT5640_R_VOL_SFT,
 			127, 0, adc_vol_tlv),
+	SOC_DOUBLE("Mono ADC Capture Switch", RT5640_DUMMY1,
+		RT5640_M_MONO_ADC_L_SFT, RT5640_M_MONO_ADC_R_SFT, 1, 1),
 	SOC_DOUBLE_TLV("Mono ADC Capture Volume", RT5640_ADC_DATA,
 			RT5640_L_VOL_SFT, RT5640_R_VOL_SFT,
 			127, 0, adc_vol_tlv),

sound/soc/codecs/rt5640.h

@@ -1971,6 +1971,10 @@
 #define RT5640_ZCD_HP_EN			(0x1 << 15)
 
 /* General Control 1 (0xfa) */
+#define RT5640_M_MONO_ADC_L			(0x1 << 13)
+#define RT5640_M_MONO_ADC_L_SFT			13
+#define RT5640_M_MONO_ADC_R			(0x1 << 12)
+#define RT5640_M_MONO_ADC_R_SFT			12
 #define RT5640_MCLK_DET				(0x1 << 11)
 
 /* Codec Private Register definition */