ASoC: rt711-sdca: add the notification when volume changed

This patch adds the return value when the volume settings were changed.
The userspace application might monitor the kcontrols to check which control changed.

Signed-off-by: Shuming Fan <shumingf@realtek.com>
Link: https://lore.kernel.org/r/20210422103235.22048-1-shumingf@realtek.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/codecs/rt711-sdca.c b/sound/soc/codecs/rt711-sdca.c
index 39848d2641c3b2dfdee33df34200bccd582ded2e..cc36739f7fcfb8223ca532b67b596fe1f604229f 100644 (file)
--- a/sound/soc/codecs/rt711-sdca.c
+++ b/sound/soc/codecs/rt711-sdca.c
@@ -509,12 +509,16 @@ static int rt711_sdca_set_gain_put(struct snd_kcontrol *kcontrol,
                (struct soc_mixer_control *)kcontrol->private_value;
        struct rt711_sdca_priv *rt711 = snd_soc_component_get_drvdata(component);
        unsigned int read_l, read_r, gain_l_val, gain_r_val;
-       unsigned int i, adc_vol_flag = 0;
+       unsigned int i, adc_vol_flag = 0, changed = 0;
+       unsigned int lvalue, rvalue;
 
        if (strstr(ucontrol->id.name, "FU1E Capture Volume") ||
                strstr(ucontrol->id.name, "FU0F Capture Volume"))
                adc_vol_flag = 1;
 
+       regmap_read(rt711->mbq_regmap, mc->reg, &lvalue);
+       regmap_read(rt711->mbq_regmap, mc->rreg, &rvalue);
+
        /* control value to 2's complement value */
        /* L Channel */
        gain_l_val = ucontrol->value.integer.value[0];
@@ -560,6 +564,11 @@ static int rt711_sdca_set_gain_put(struct snd_kcontrol *kcontrol,
                gain_r_val &= 0xffff;
        }
 
+       if (lvalue != gain_l_val || rvalue != gain_r_val)
+               changed = 1;
+       else
+               return 0;
+
        for (i = 0; i < 3; i++) { /* retry 3 times at most */
                /* Lch*/
                regmap_write(rt711->mbq_regmap, mc->reg, gain_l_val);
@@ -573,7 +582,7 @@ static int rt711_sdca_set_gain_put(struct snd_kcontrol *kcontrol,
                        break;
        }
 
-       return i == 3 ? -EIO : 0;
+       return i == 3 ? -EIO : changed;
 }
 
 static int rt711_sdca_set_gain_get(struct snd_kcontrol *kcontrol,