On Fri, Jul 24, 2020 at 7:16 PM Mark Brown broonie@kernel.org wrote:
On Fri, Jul 24, 2020 at 03:07:31PM +0800, Tzung-Bi Shih wrote:
Commit 4e872a46823c ("ASoC: dapm: Don't force card bias level to be updated") stops to force update bias_level on card. If card doesn't provide set_bias_level callback, the snd_soc_dapm_set_bias_level() is equivalent to NOP for card device.
As a result, dapm_pre_sequence_async() doesn't change the bias_level of card device correctly. Thus, pm_runtime_get_sync() would be called in dapm_pre_sequence_async() without symmetric pm_runtime_put() in dapm_post_sequence_async().
Don't call pm_runtime_* on card device.
Why is this a good fix, as opposed to only skipping the set_bias_level() bit?
Did you mean: skip to call snd_soc_dapm_set_bias_level() in dapm_pre_sequence_async() and dapm_post_sequence_async()?
If so, skipping snd_soc_dapm_set_bias_level() won't fix the issue. The runtime_usage increases in pm_runtime_get() and decreases in pm_runtime_put().
Besides, snd_soc_dapm_set_bias_level() calls card->set_bias_level() and card->set_bias_level_post() if any. Skip to call snd_soc_dapm_set_bias_level() couldn't be a good idea. It may change some existing code behavior.