Hi Laurent and Mauro, On Mon, Jun 11, 2012 at 10:30 AM, Mauro Carvalho Chehab <mchehab@xxxxxxxxxx> wrote: > Em 07-06-2012 15:26, Ezequiel Garcia escreveu: >> Hi all, >> >> (I hope this is a genuine question, and I'm not avoiding my own homework here.) >> >> I'm trying to support the audio part of the stk1160 usb bridge >> (similar to em28xx). >> Currently, the snd-usb-audio module is being loaded when I physically >> plug my device, >> but I can't seem to capture any sound with vlc. > > Laurent already explained why snd-usb-audio is loaded. >> >> I still have to research and work a lot to understand the connection >> between my device >> and alsa, and altough I could write a working module similar to >> em28xx-alsa.ko, I still >> can't figure out why do I need to write one in the first place. > > On em28xx, some devices use UAC (USB Audio Class), while others use a proprietary > vendor class protocol. The em28xx-alsa module is used only for the devices with a > vendor class. >> >> Why is this module suffficient for gspca microphone devices (gspca, to name one) >> and why is a new alsa driver needed for em28xx (or stk1160)? > > On em28xx, even the ones that use UAC require some configuration, for audio to work. > > some setup is required to configure the audio input associated with a video input, > and to enable clock for the audio sampler. Such setup is made when a video input is > selected. You likely need something similar for stk1160. > It is *much* clear now, thanks to both. Ezequiel. -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
