path: root/sound
diff options
authorAnssi Hannula <anssi.hannula@iki.fi>2013-09-01 14:36:47 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-09-26 17:18:14 -0700
commit686edbc09d22070e8ff3edaf7a6f53f80b4517b0 (patch)
treea3223acab78b1ebbf8fc4ac8c46dd831523e4ca1 /sound
parentdc780f7fc64b6ca11854cd5ac724b85fa1853495 (diff)
ALSA: hda - hdmi: Fallback to ALSA allocation when selecting CA
commit 18e391862cceaf43ddb8eb5cca05e1a83abdebaa upstream. hdmi_channel_allocation() tries to find a HDMI channel allocation that matches the number channels in the playback stream and contains only speakers that the HDMI sink has reported as available via EDID. If no such allocation is found, 0 (stereo audio) is used. Using CA 0 causes the audio causes the sink to discard everything except the first two channels (front left and front right). However, the sink may be capable of receiving more channels than it has speakers (and then perform downmix or discard the extra channels), in which case it is preferable to use a CA that contains extra channels than to use CA 0 which discards all the non-stereo channels. Additionally, it seems that HBR (HD) passthrough output does not work on Intel HDMI codecs when CA is set to 0 (possibly the codec zeroes channels not present in CA). This happens with all receivers that report a 5.1 speaker mask since a HBR stream is carried on 8 channels to the codec. Add a fallback in the CA selection so that the CA channel count at least matches the stream channel count, even if the stream contains channels not present in the sink speaker descriptor. Thanks to GrimGriefer at OpenELEC forums for discovering that changing the sink speaker mask allowed HBR output. Reported-by: GrimGriefer Reported-by: Ashecrow Reported-by: Frank Zafka <kafkaesque1978@gmail.com> Reported-by: Peter Fr├╝hberger <fritsch@xbmc.org> Signed-off-by: Anssi Hannula <anssi.hannula@iki.fi> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'sound')
1 files changed, 11 insertions, 0 deletions
diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
index 83c1ad54ae7..b5375ed022d 100644
--- a/sound/pci/hda/patch_hdmi.c
+++ b/sound/pci/hda/patch_hdmi.c
@@ -553,6 +553,17 @@ static int hdmi_channel_allocation(struct hdmi_eld *eld, int channels)
+ if (!ca) {
+ /* if there was no match, select the regular ALSA channel
+ * allocation with the matching number of channels */
+ for (i = 0; i < ARRAY_SIZE(channel_allocations); i++) {
+ if (channels == channel_allocations[i].channels) {
+ ca = channel_allocations[i].ca_index;
+ break;
+ }
+ }
+ }
snd_print_channel_allocation(eld->info.spk_alloc, buf, sizeof(buf));
snd_printdd("HDMI: select CA 0x%x for %d-channel allocation: %s\n",
ca, channels, buf);