[PATCH 5.15 023/135] ASoC: da7219: Fix change notifications for tone generator frequency

Greg Kroah-Hartman
2022-05-10T13:58:09Z

From: Mark Brown <broonie@kernel.org>

commit 08ef48404965cfef99343d6bbbcf75b88c74aa0e upstream.

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>
Reviewed-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220420133437.569229-1-broonie@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
sound/soc/codecs/da7219.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)

--- a/sound/soc/codecs/da7219.c
+++ b/sound/soc/codecs/da7219.c
@@ -446,7 +446,7 @@ static int da7219_tonegen_freq_put(struc
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(struc
* 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;
}