On Wed, 24 Feb 2021 13:08:55 +0100, Jaroslav Kysela wrote: > > Dne 24. 02. 21 v 12:43 Takashi Iwai napsal(a): > > >>> So far, a user control is merely storing the value, let read/write via > >>> the control API. That's all, and nothing wrong can happen just by > >>> that. Now if it interacts with other subsystem... > >>> > >>> A more serious concern is rather the fragility of the setup; for > >>> enabling the mute LED control, you'd have to create a new user-space > >>> control, the function of the control has to be ignored by some > >>> application and some not, etc. This has to be done on each machine > >> > >> You're using "ignore", but as I explained before, the user space switch will > >> be used in the whole chain: > >> > >> capture stream -> > >> alsa-lib mute switch / silence PCM stream -> > >> PA mute switch / silence PCM stream > >> > >> So PA can use this switch like the traditional hardware mute switch. > > > > Does it mean PA would work as of now without any change? Or does it > > need patching? > > Yes, no PA modifications are required with my mechanism. The PA will just see > the new user space control - mute switch - created in alsa-lib - which will be > synced the internal PA path mute state like for the hardware mute > switch. OK, but how would we create and manage the user control element? And why it has to be user control? thanks, Takashi
