The kcontrol put callback is expected to return 1 when there is change in HW or when the update is acknowledged by driver. This would ensure that change notifications are sent to subscribed applications. Filter out duplicate updates in Mixer driver.
Fixes: 05bb3d5ec64a ("ASoC: tegra: Add Tegra210 based Mixer driver") Signed-off-by: Sameer Pujar spujar@nvidia.com Suggested-by: Jaroslav Kysela perex@perex.cz Suggested-by: Mark Brown broonie@kernel.org --- sound/soc/tegra/tegra210_mixer.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/sound/soc/tegra/tegra210_mixer.c b/sound/soc/tegra/tegra210_mixer.c index 55e6177..d2d1946 100644 --- a/sound/soc/tegra/tegra210_mixer.c +++ b/sound/soc/tegra/tegra210_mixer.c @@ -210,6 +210,9 @@ static int tegra210_mixer_put_gain(struct snd_kcontrol *kcontrol, id = (reg - TEGRA210_MIXER_GAIN_CFG_RAM_ADDR_0) / TEGRA210_MIXER_GAIN_CFG_RAM_ADDR_STRIDE;
+ if (mixer->gain_value[id] == ucontrol->value.integer.value[0]) + return 0; + mixer->gain_value[id] = ucontrol->value.integer.value[0];
err = tegra210_mixer_configure_gain(cmpnt, id, instant_gain);