{"action":"created","issue":{"url":"https://api.github.com/repos/raspberrypi/linux/issues/1000","labels_url":"https://api.github.com/repos/raspberrypi/linux/issues/1000/labels{/name}","comments_url":"https://api.github.com/repos/raspberrypi/linux/issues/1000/comments","events_url":"https://api.github.com/repos/raspberrypi/linux/issues/1000/events","html_url":"https://github.com/raspberrypi/linux/issues/1000","id":84085452,"number":1000,"title":"alsa: multichannel PCM unsupported","user":{"login":"wm4","id":1387750,"avatar_url":"https://avatars.githubusercontent.com/u/1387750?v=3","gravatar_id":"","url":"https://api.github.com/users/wm4","html_url":"https://github.com/wm4","followers_url":"https://api.github.com/users/wm4/followers","following_url":"https://api.github.com/users/wm4/following{/other_user}","gists_url":"https://api.github.com/users/wm4/gists{/gist_id}","starred_url":"https://api.github.com/users/wm4/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/wm4/subscriptions","organizations_url":"https://api.github.com/users/wm4/orgs","repos_url":"https://api.github.com/users/wm4/repos","events_url":"https://api.github.com/users/wm4/events{/privacy}","received_events_url":"https://api.github.com/users/wm4/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":7,"created_at":"2015-06-02T15:59:56Z","updated_at":"2015-06-04T19:14:24Z","closed_at":null,"body":"Apparently this doesn't work yet. If I interpret [this](https://github.com/raspberrypi/linux/blob/rpi-3.18.y/sound/arm/bcm2835-pcm.c#L31) correctly, there is no kernel support for this yet. If I force ALSA to output more than 2 channels, none of them seem to arrive at the receiver either (unfortunately my receiver doesn't show the PCM format it gets).\r\n\r\nI wonder what the 8 sub devices are for?"},"comment":{"url":"https://api.github.com/repos/raspberrypi/linux/issues/comments/109016309","html_url":"https://github.com/raspberrypi/linux/issues/1000#issuecomment-109016309","issue_url":"https://api.github.com/repos/raspberrypi/linux/issues/1000","id":109016309,"user":{"login":"wm4","id":1387750,"avatar_url":"https://avatars.githubusercontent.com/u/1387750?v=3","gravatar_id":"","url":"https://api.github.com/users/wm4","html_url":"https://github.com/wm4","followers_url":"https://api.github.com/users/wm4/followers","following_url":"https://api.github.com/users/wm4/following{/other_user}","gists_url":"https://api.github.com/users/wm4/gists{/gist_id}","starred_url":"https://api.github.com/users/wm4/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/wm4/subscriptions","organizations_url":"https://api.github.com/users/wm4/orgs","repos_url":"https://api.github.com/users/wm4/repos","events_url":"https://api.github.com/users/wm4/events{/privacy}","received_events_url":"https://api.github.com/users/wm4/received_events","type":"User","site_admin":false},"created_at":"2015-06-04T19:14:24Z","updated_at":"2015-06-04T19:14:24Z","body":"Raising the max. channel count to 8 does work. I can output 6 channels, and they all arrive separately on the receiver. 8 channels also appears to work, except I can't test this properly because my receiver can do 5.1 only.\r\n\r\nThe only problem is that the ALSA API still doesn't report any channel maps, so this part still needs to be implemented. Haven't looked into it.\r\n\r\nDTS-HD passthrough also almost works. I just had to raise the max. channel count to 8, and the max. samplerate to 192000 in the spdif device."}}