ASoC: sgtl5000: Cleanup bias level transitions

Set the CODEC driver's suspend_bias_off flag rather than manually going to
SND_SOC_BIAS_OFF in suspend and SND_SOC_BIAS_STANDBY in resume. This makes
the code a bit shorter and cleaner.

Since the ASoC core now takes care of setting the bias level to
SND_SOC_BIAS_OFF when removing the CODEC there is no need to do it manually
anymore either.

The manual transition to SND_SOC_BIAS_STANDBY at the end of CODEC probe()
can also be removed as the core will automatically do this after the CODEC
has been probed.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/sgtl5000.c

@@ -1073,26 +1073,6 @@ static bool sgtl5000_readable(struct device *dev, unsigned int reg)
 	}
 }
 
-#ifdef CONFIG_SUSPEND
-static int sgtl5000_suspend(struct snd_soc_codec *codec)
-{
-	sgtl5000_set_bias_level(codec, SND_SOC_BIAS_OFF);
-
-	return 0;
-}
-
-static int sgtl5000_resume(struct snd_soc_codec *codec)
-{
-	/* Bring the codec back up to standby to enable regulators */
-	sgtl5000_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
-
-	return 0;
-}
-#else
-#define sgtl5000_suspend NULL
-#define sgtl5000_resume  NULL
-#endif	/* CONFIG_SUSPEND */
-
 /*
  * sgtl5000 has 3 internal power supplies:
  * 1. VAG, normally set to vdda/2
@@ -1352,11 +1332,6 @@ static int sgtl5000_probe(struct snd_soc_codec *codec)
 	 */
 	snd_soc_write(codec, SGTL5000_DAP_CTRL, 0);
 
-	/* leading to standby state */
-	ret = sgtl5000_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
-	if (ret)
-		goto err;
-
 	return 0;
 
 err:
@@ -1373,8 +1348,6 @@ static int sgtl5000_remove(struct snd_soc_codec *codec)
 {
 	struct sgtl5000_priv *sgtl5000 = snd_soc_codec_get_drvdata(codec);
 
-	sgtl5000_set_bias_level(codec, SND_SOC_BIAS_OFF);
-
 	regulator_bulk_disable(ARRAY_SIZE(sgtl5000->supplies),
 						sgtl5000->supplies);
 	regulator_bulk_free(ARRAY_SIZE(sgtl5000->supplies),
@@ -1387,9 +1360,8 @@ static int sgtl5000_remove(struct snd_soc_codec *codec)
 static struct snd_soc_codec_driver sgtl5000_driver = {
 	.probe = sgtl5000_probe,
 	.remove = sgtl5000_remove,
-	.suspend = sgtl5000_suspend,
-	.resume = sgtl5000_resume,
 	.set_bias_level = sgtl5000_set_bias_level,
+	.suspend_bias_off = true,
 	.controls = sgtl5000_snd_controls,
 	.num_controls = ARRAY_SIZE(sgtl5000_snd_controls),
 	.dapm_widgets = sgtl5000_dapm_widgets,