Hi Takashi
Takashi-san
I created this patch and its git-log, but please fixup it if needed.
I would split this again to two patches, one for adding snd_card_disconnect_sync(), and another for adding snd_pcm_stop() call at snd_pcm_dev_disconnect().
Basically the latter is for the drivers that don't handle the PCM stop at disconnection explicitly, and it's not mandatory when the driver's pcm dev_disconnect callback handles it.
Also, since these changes are about ALSA core, and at least the PCM-stop one is intrusive and may have influences on the behavior of other drivers, I'd like to test with usb-audio before landing to ASoC world. Once when confirmed, I'll publish a persistent branch containing these API changes and let Mark pull it.
Thanks. I will re-post [2/3] [3/3] part patch on top of your persistent branch.
Best regards --- Kuninori Morimoto