The tone generator frequency control just returns 0 on successful write, not a boolean value indicating if there was a change or not. Compare what was written with the value that was there previously so that notifications are generated appropriately when the value changes.

Signed-off-by: Mark Brown broonie@kernel.org --- sound/soc/codecs/da7219.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/sound/soc/codecs/da7219.c b/sound/soc/codecs/da7219.c index a28d3601b932..7fdef38ed8cd 100644 --- a/sound/soc/codecs/da7219.c +++ b/sound/soc/codecs/da7219.c @@ -446,7 +446,7 @@ static int da7219_tonegen_freq_put(struct snd_kcontrol *kcontrol, struct soc_mixer_control *mixer_ctrl = (struct soc_mixer_control *) kcontrol->private_value; unsigned int reg = mixer_ctrl->reg; - __le16 val; + __le16 val_new, val_old; int ret;

/* @@ -454,13 +454,19 @@ static int da7219_tonegen_freq_put(struct snd_kcontrol *kcontrol, * Therefore we need to convert to little endian here to align with * HW registers. */ - val = cpu_to_le16(ucontrol->value.integer.value[0]); + val_new = cpu_to_le16(ucontrol->value.integer.value[0]);

mutex_lock(&da7219->ctrl_lock); - ret = regmap_raw_write(da7219->regmap, reg, &val, sizeof(val)); + ret = regmap_raw_read(da7219->regmap, reg, &val_old, sizeof(val_old)); + if (ret == 0 && (val_old != val_new)) + ret = regmap_raw_write(da7219->regmap, reg, + &val_new, sizeof(val_new)); mutex_unlock(&da7219->ctrl_lock);

- return ret; + if (ret < 0) + return ret; + + return val_old != val_new; }