ASoC: adau17x1: Do not reload dsp-fw if samplerate has not changed

Reloading fw causes an audiable popping sound, we can avoid this
by not reloading if the samplerate is the same as before.

Signed-off-by: Danny Smith <dannys@axis.com>
Signed-off-by: Robert Rosengren <robert.rosengren@axis.com>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/codecs/adau17x1.c b/sound/soc/codecs/adau17x1.c
index 12bf24c26818a3ff046a426f56d0cebb356be9a2..ae41edd1c406b4fa38d1aed55670cfd227ee660a 100644 (file)
--- a/sound/soc/codecs/adau17x1.c
+++ b/sound/soc/codecs/adau17x1.c
@@ -843,6 +843,15 @@ int adau17x1_setup_firmware(struct snd_soc_component *component,
        struct adau *adau = snd_soc_component_get_drvdata(component);
        struct snd_soc_dapm_context *dapm = snd_soc_component_get_dapm(component);
 
+       /* Check if sample rate is the same as before. If it is there is no
+        * point in performing the below steps as the call to
+        * sigmadsp_setup(...) will return directly when it finds the sample
+        * rate to be the same as before. By checking this we can prevent an
+        * audiable popping noise which occours when toggling DSP_RUN.
+        */
+       if (adau->sigmadsp->current_samplerate == rate)
+               return 0;
+
        snd_soc_dapm_mutex_lock(dapm);
 
        ret = regmap_read(adau->regmap, ADAU17X1_DSP_SAMPLING_RATE, &dspsr);