On Mon, 23 Mar 2020 18:06:43 +0100, Takashi Iwai wrote: > > USB-audio driver registers the card and its devices at each probe of > USB interface, while trying to append a USB substream into the empty > PCM stream slot. This works for most cases where the all PCM streams > are declared in the single interface description. However, when the > device provides multiple individual interfaces, this may up with > pushing a new stream into the existing snd_pcm object that has been > already registered. From the driver perspective, it's OK, but it > doesn't work for PulseAudio and others because they manage in the card > registration level, hence they'll miss this new device creation. > > This patch tries to warn such a too-late-appended stream, and also > tries to put rather into a new snd_pcm object. > > If we get a report from a user about this, we may add it to an entry > for snd_usb_registration_quirk(). > > Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> Let's scratch this. It's better to be put together with a generic module option that allows specifying the delayed registration for the given device, and show the warning at the time of snd_card_register() call instead. Will respin the improved version later. Takashi
