[alsa-devel] Getting ELD and available chmaps without opening device?

Hi all,

I want to read the ELD of a HDMI sink while another playback is ongoing.

I have the device name (e.g. "hdmi:CARD=NVidia,DEV=0"), and normally I'd open the device, use snd_pcm_info() to get snd_pcm_info_t with which I can use snd_pcm_info_get_card() and snd_pcm_info_get_device() to get the necessary information to access the control with snd_ctl_open(), snd_hctl_open_ctl() etc.

However, since another playback is ongoing I can't open the device. Is there another way I'm missing, or do I simply have to magically know the card/device numbers (which in my case is possible with some tricks since the playback is in the same application, but I'd guess that might not always be the case)?

Same affects available chmaps from what I can see.